U.S. patent application number 13/075605 was filed with the patent office on 2011-10-06 for nitrogen-containing carbon alloy, process of producing the same, and carbon catalyst containing the same.
This patent application is currently assigned to FUJIFILM CORPORATION. Invention is credited to JUN TANABE.
Application Number | 20110245071 13/075605 |
Document ID | / |
Family ID | 44710322 |
Filed Date | 2011-10-06 |
United States Patent
Application |
20110245071 |
Kind Code |
A1 |
TANABE; JUN |
October 6, 2011 |
NITROGEN-CONTAINING CARBON ALLOY, PROCESS OF PRODUCING THE SAME,
AND CARBON CATALYST CONTAINING THE SAME
Abstract
A nitrogen-containing carbon alloy obtained by baking an organic
material having a nitrogen-containing crystalline organic compound
having a molecular weight of 60 to 2000, wherein the
nitrogen-containing crystalline organic compound excludes a
nitrogen-containing metal complex.
Inventors: |
TANABE; JUN; (KANAGAWA,
JP) |
Assignee: |
FUJIFILM CORPORATION
TOKYO
JP
|
Family ID: |
44710322 |
Appl. No.: |
13/075605 |
Filed: |
March 30, 2011 |
Current U.S.
Class: |
502/180 |
Current CPC
Class: |
B01J 27/24 20130101;
H01M 4/608 20130101; H01M 4/60 20130101; Y02E 60/50 20130101; H01M
4/923 20130101; C01B 32/05 20170801; Y02E 60/13 20130101; H01M
4/587 20130101; B01J 37/086 20130101; H01M 2008/1095 20130101; Y02E
60/10 20130101; H01M 12/08 20130101; H01G 11/30 20130101; H01M
4/9008 20130101; H01M 4/58 20130101; B01J 23/745 20130101; H01M
10/0525 20130101; B01J 23/75 20130101; H01G 11/34 20130101; H01M
4/9083 20130101; B01J 31/22 20130101; B01J 35/1019 20130101 |
Class at
Publication: |
502/180 |
International
Class: |
B01J 21/18 20060101
B01J021/18 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 30, 2010 |
JP |
2010-079924 |
Claims
1. A nitrogen-containing carbon alloy obtained by baking an organic
material comprising a nitrogen-containing crystalline organic
compound having a molecular weight of 60 to 2000, wherein the
nitrogen-containing crystalline organic compound excludes a
nitrogen-containing metal complex.
2. The nitrogen-containing carbon alloy according to claim 1,
wherein the organic material further comprises at least one of an
inorganic metal and an inorganic metal salt.
3. The nitrogen-containing carbon alloy according to claim 1,
wherein the nitrogen-containing crystalline organic compound is a
nitrile compound, an amide compound or a quinacridone compound.
4. The nitrogen-containing carbon alloy according to claim 1,
wherein the nitrogen-containing crystalline organic compound has at
least one group selected from the group consisting of a nitrile
group, an amido group and 4-quinolone structure, and an unsaturated
bond per molecule.
5. The nitrogen-containing carbon alloy according to claim 4,
wherein the nitrogen-containing crystalline organic compound has at
least one selected from the group consisting of a nitrile group and
an amido group, at least one selected from the group consisting of
a nitrile group, an amido group, a halogen atom, and a hydroxyl
group, and an unsaturated bond per molecule.
6. The nitrogen-containing carbon alloy according to claim 1,
wherein the nitrogen-containing crystalline organic compound is a
pigment.
7. The nitrogen-containing carbon alloy according to claim 1,
wherein the nitrogen-containing crystalline organic compound has a
nitrogen content of 0.1% to 55% by mass.
8. The nitrogen-containing carbon alloy according to claim 1,
wherein the organic material is a volatile-retardant compound
having a .DELTA.TG value of -95% to -0.1% at 400.degree. C. in a
nitrogen atmosphere.
9. The nitrogen-containing carbon alloy according to claim 1,
wherein the baking is carried out at a baking temperature of
500.degree. to 1000.degree. C. in a stream of inert gas or
non-oxidizing gas.
10. The nitrogen-containing carbon alloy according to claim 9,
wherein the inert gas or non-oxidizing gas flows at a flow rate of
0.01 to 2.0 l/min per 36 mm inner diameter.
11. A process for producing the nitrogen-containing carbon alloy
according to claim 2, comprising: mixing the nitrogen-containing
crystalline organic compound and the at least one of the inorganic
metal and the inorganic metal salt; raising a temperature of the
mixture from room temperature to a carbonization temperature of the
mixture in an inert atmosphere at a rate of 1.degree. C./min to
1000.degree. C./min; maintaining the mixture at a temperature of
500.degree. to 1000.degree. C. for 0.1 to 100 hours to achieve
carbonization; and cooling the carbonized mixture from the
carbonization temperature to room temperature.
12. A carbon catalyst comprising the nitrogen-containing carbon
alloy according to claim 1.
13. A fuel cell comprising the carbon catalyst according to claim
12 and a polyelectrolyte.
14. An electrical storage device comprising the carbon catalyst
according to claim 12.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] The present application claims priority from Japanese Patent
Application No. 2010-079924 filed on Mar. 30, 2010, the entire
content of which is incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] This invention relates to a nitrogen-containing carbon
alloy, a process of producing the carbon alloy, and a carbon
catalyst containing the carbon alloy. More particularly, it relates
to an N-containing carbon alloy obtained from a low-molecular
N-containing crystalline organic compound, a process of producing
the same, and a carbon catalyst containing the same.
[0004] 2. Description of the Related Art
[0005] Catalysts based on noble metals, such as platinum and
palladium, have been applied for their high oxygen reduction
activity to, for example, solid polyelectrolyte fuel cells used in
automobiles, and domestic power and heat supply systems. However,
the noble metal-based catalysts are too costly to be used even more
widely.
[0006] Research and development have therefore been invested into
platinum-free catalysts or catalysts with greatly reduced use of
platinum. For example, JP 2007-26746A proposes a catalyst having
carbon alloy obtained by baking a polymer resulting from
polymerization of a mixture of a precursor of a resin, such as
polyfurfuryl alcohol, phenol formaldehyde or melamine resin, and a
metal complex, such as cobalt phthalocyanine or iron
phthalocyanine. Such a carbon alloy catalyst is known to have high
oxygen reduction activity because it is obtained by uniformly
dispersing the metal complex in a resin precursor followed by
decomposing other than the metal, for example, phthalocyanine
moiety so that the metal is uniformly distributed in the catalyst
as reported in "Proceedings of the '09 Meeting and Workshop of Fuel
Cell-Related Catalyst Division in Catalyst Society of Japan".
[0007] JP 2009-173627A describes an electrode catalyst for fuel
cells which is obtained by heating a mixture of a metal complex and
an organic cyclic compound. JP 2009-234918A discloses a catalyst
having a modified metal complex obtained by subjecting a
mononuclear-metal complex having an aromatic skeleton to a
modification treatment selected from a heat treatment, an
irradiation treatment with a radiation, and a discharge
treatment.
[0008] The problem of these processes is that the polymer material
contains low-molecular impurities, such as a solvent, and needs
removal of the impurities, which makes the production process
complicated. In contrast, processes starting with a low molecular
compound are advantageous in that the low molecular compound may
previously be purified to provide a high purity precursor. This
offers a broader choice of precursor materials.
[0009] Carbon alloys prepared from low molecular compounds include
those obtained by baking a metal complex and an unsaturated
compound as disclosed in JP 2009-39623A and those obtained by
baking a metal complex and a polycyclic organic compound having at
least two hetero atoms on the same ring as disclosed in JP
2010-270107A. However, metal complexes are difficult to purify, and
the unsaturated compound is structurally limited because it must
react with the ligand of the metal complex. Due to these problems
it is not easy to stably prepare a carbon alloy of high oxygen
reduction activity, and the advantage of using a low molecular
compound is hardly achieved. "Jun Murayama, Carbon, 48, 3271
(2010)" reports preparation of a carbon alloy by baking a mixture
of a nitrogen-containing polycyclic organic compound, ferric
gluconate, and magnesium acetate, but the oxygen reduction activity
of this carbon alloy catalyst is lower than that of the carbon
alloys of polymer origin so that it is difficult to eliminate the
need to use a noble metal such as platinum or palladium.
[0010] On the other hand, metal-free low molecular compounds are
free of the problems, such as difficulty of purification and
structural limitation. Using a metal-free low molecular compound,
nevertheless, poses the following problem. "Jun Murayama and Ikuo
Abe, Journal of the Electrochemical Society, 154(3), B297 (2007)",
for example, reports a case in which a mixture of an amino acid,
glucose, and iron lactate is dehydrated and baked. The report
reveals that the amino acid alone decomposes at 350.degree. C. and
cannot carbonize, indicating the difficulty in carbonizing a
metal-free low molecular compound by baking. It has thus been
believed by those skilled in the art that a carbon alloy is not
obtained from a metal-free low molecular compound.
SUMMARY
[0011] An object of the invention is to provide a carbon alloy
which has a metal other than noble metals uniformly supported
therein and thereby exhibits sufficiently high oxygen reduction
activity and which is obtained by baking a low-molecular organic
compound that is easy to purify and may have a wide choice of
structure; a process of producing the carbon alloy; and a carbon
catalyst containing the carbon alloy.
[0012] As a result of extensive investigation, the inventors of the
present invention have found that an N-containing carbon alloy with
sufficiently high oxygen reduction activity is obtainable by baking
an organic material having an N-containing crystalline organic
compound with a molecular weight of 60 to 2000. They have also
found that, when an inorganic metal or an inorganic metal salt is
admixed with the N-containing crystalline organic compound, there
is obtained an N-containing carbon alloy having the metal uniformly
supported therein and exhibiting further increased oxygen reduction
activity. The invention has thus been completed based on these
findings.
[0013] Although a metal-free low molecular compound vaporizes on
baking, vaporization of the compound on baking is suppressed by
crystallizing the compound to impart increased intermolecular
action. By the use of the crystallized compound, carbon alloys
having various interstitial structures corresponding to the crystal
structure of the crystallized compound can easily be prepared,
which allows for controlling the catalyst activity or electric
conductivity that is closely related to the interstitial
structure.
[0014] There is a report that it is desirable to remove a metal
oxide and the like from organic materials (see JP-2009-234918). To
the contrary, the inventors have ascertained that better effects
are obtained when in using an organic material containing at least
one of an inorganic metal and an inorganic metal salt. It is
considered that, when an N-containing crystalline low molecular
compound and an inorganic metal or an inorganic metal salt are used
in combination, the metal atoms and nitrogen atoms, which are
positioned along the crystal edges with great regularity and
uniformity to exert mutual action with each other previously and,
as a result, a catalytically-competent nitrogen to metal ratio is
achieved spontaneously to provide a carbon alloy having high oxygen
reduction activity.
[0015] The above objects of the invention are accomplwashed by the
provision of the following subject matter.
<1> A nitrogen-containing carbon alloy obtained by baking an
organic material having a nitrogen-containing crystalline organic
compound having a molecular weight of 60 to 2000, wherein the
nitrogen-containing crystalline organic compound excludes a
nitrogen-containing metal complex. <2> The
nitrogen-containing carbon alloy according to <1>, wherein
the organic material further has at least one of an inorganic metal
and an inorganic metal salt. <3> The nitrogen-containing
carbon alloy according to <1>, wherein the
nitrogen-containing crystalline organic compound is a nitrile
compound, an amide compound or a quinacridone compound. <4>
The nitrogen-containing carbon alloy according to <1>,
wherein the nitrogen-containing crystalline organic compound has at
least one group selected from the group consisting of a nitrile
group, an amido group and 4-quinolone structure, and an unsaturated
bond per molecule. <5> The nitrogen-containing carbon alloy
according to <4>, wherein the nitrogen-containing crystalline
organic compound has at least one selected from the group
consisting of a nitrile group and an amido group, at least one
selected from the group consisting of a nitrile group, an amido
group, a halogen atom, and a hydroxyl group, and an unsaturated
bond per molecule. <6> The nitrogen-containing carbon alloy
according to <1>, wherein the nitrogen-containing crystalline
organic compound is a pigment. <7> The nitrogen-containing
carbon alloy according to <1>, wherein the
nitrogen-containing crystalline organic compound has a nitrogen
content of 0.1% to 55% by mass. <8> The nitrogen-containing
carbon alloy according to <1>, wherein the organic material
is a volatile-retardant compound having a .DELTA.TG value of -95%
to -0.1% at 400.degree. C. in a nitrogen atmosphere. <9> The
nitrogen-containing carbon alloy according to <1>, wherein
the baking is carried out at a baking temperature of 500.degree. to
1000.degree. C. in a stream of inert gas or non-oxidizing gas.
<10> The nitrogen-containing carbon alloy according to
<9>, wherein the inert gas or non-oxidizing gas flows at a
flow rate of 0.01 to 2.0 l/min per 36 mm inner diameter. <11>
A process for producing the nitrogen-containing carbon alloy
according to <2>, having: mixing the nitrogen-containing
crystalline organic compound and the at least one of the inorganic
metal and the inorganic metal salt; raising a temperature of the
mixture from room temperature to a carbonization temperature of the
mixture in an inert atmosphere at a rate of 1.degree. C./min to
1000.degree. C./min; maintaining the mixture at a temperature of
500.degree. to 1000.degree. C. for 0.1 to 100 hours to achieve
carbonization; and cooling the carbonized mixture from the
carbonization temperature to room temperature. <12> A carbon
catalyst having the nitrogen-containing carbon alloy according to
<1>. <13> A fuel cell having the carbon catalyst
according to <12> and a polyelectrolyte. <14> An
electrical storage device having the carbon catalyst according to
<12>.
[0016] According to the invention, an N-containing carbon alloy
having sufficiently high oxygen reduction activity is obtained by
baking an organic material containing a low molecular crystalline
N-containing organic compound that is easy to purify and may have a
wide choice of structure. When an inorganic metal or an inorganic
metal salt is admixed with the crystalline N-containing organic
compound, there is obtained an N-containing carbon alloy having the
metal uniformly supported therein, exhibiting further increased
oxygen reduction activity, and having a desired lattice structure.
The N-containing carbon alloy is useful as a carbon catalyst. The
carbon catalyst is applicable to fuel cells and environmental
catalysts. The invention also provides a process for producing the
N-containing carbon alloy.
BRIEF DESCRIPTION OF DRAWINGS
[0017] FIG. 1 schematically illustrates a fuel cell having a carbon
alloy of the invention.
[0018] FIG. 2 schematically illustrates an electrical double-layer
capacitor having a carbon alloy of the invention.
[0019] FIG. 3 graphically represents voltage-current density curves
of the fuel cells of Examples 2, 4, 5, 8, 10, 14, 21, and 24 and
Comparative Example 4.
DETAILED DESCRIPTION OF INVENTION
[0020] The term "Hammett constant op" that will be used in the
following description is briefly explained below. The Hammett's
rule is an empirical rule proposed by L. P. Hammett in 1935 in an
attempt to quantitatively discuss the influences of a substituent
of a benzene derivative on the reaction or equilibrium, the
validity of which is now generally admitted. Substituent constants
obtained by the Hammett's rule include .sigma.p and .sigma.m
values. These values are found in many general books, for example,
J. A. Dean (ed.), Lange's Handbook of Chemistry, the 12th Ed.,
MacGraw-Hill (1979) and Kagakuno Ryoiki, Extra Ed., No. 122, pp.
96-103, Nankodo (1979). In the following description, various
substituents will be limited or described in terms of Hammett
constants .sigma.p. This does not mean that intended substituents
are limited to those substituents the .sigma.p value of which is
known from literature, and intended substituents include any
substituent of which the .sigma.p value is not found in literature
but seems to fall within a recited range when determined based on
Hammett's rule. While the pigments represented by formulae (1) and
(2) that will be described later for use in the invention are not
benzene derivatives, the electronic effect of their substituent
will be represented by the measure .sigma.p irrespective of the
position of the substituent. Note that the .sigma.p values will be
used in that sense hereinafter.
[0021] As used herein, the term "substituent" means any atom or
group of atomics capable of substitution. Examples of the
substituent include halogen atoms (e.g., fluorine, chlorine,
bromine, and iodine), a hydroxyl group, a cyano group, aliphatic
groups (e.g., aralkyl, cycloalkyl, and active methine), an aryl
group (which may be bonded at any position thereof), a heterocyclic
group (which may be bonded at any position thereof), an acyl group,
aliphatic oxy groups (e.g., alkoxy, alkyleneoxy, or a group having
repeated ethyleneoxy or propyleneoxy units), an aryloxy group, a
heterocyclic oxy group, an aliphatic carbonyl group, an
arylcarbonyl group, a heterocyclic carbonyl group, an aliphatic
oxycarbonyl group, an aryloxycarbonyl group, a heterocyclic
oxycarbonyl group, a carbamoyl group, a sulfonylcarbamoyl group, an
acylcarbamoyl group, a sulfamoylcarbamoyl group, a thiocarbamoyl
group, an aliphatic carbonyloxy group, an aryloxycarbonyloxy group,
a heterocyclic carbonyloxy group, an amino group, an aliphatic
amino group, an arylamino group, a heterocyclic amino group, an
acylamino group, an aliphatic oxyamino group, an aryloxyamino
group, a sulfamoylamino group, an acylsulfamoylamino group, an
oxamoylamino group, an aliphatic oxycarbonylamino group, an
aryloxycarbonylamino group, a heterocyclic oxycarbonylamino group,
a carbamoylamino group, a mercapto group, an aliphatic thio group,
an arylthio group, a heterocyclic thio group, an alkylsulfinyl
group, an arylsulfinyl group, an aliphatic sulfonyl group, an
arylsulfonyl group, a heterocyclic sulfonyl group, an aliphatic
sulfonylureido group, an arylsulfonylureido group, a heterocyclic
sulfonylureido group, an aliphatic sulfonyloxy group, an
arylsulfonyloxy group, a heterocyclic sulfonyloxy group, a
sulfamoyl group, an aliphatic sulfamoyl group, an arylsulfamoyl
group, a heterocyclic sulfamoyl group, an acylsulfamoyl group, a
sulfonylsulfamoyl group or a salt thereof, a carbamoylsulfamoyl
group, a sulfonamido group, an aliphatic ureido group, an
arylureido group, a heterocyclic ureido group, an aliphatic
sulfonamido group, an arylsulfonamido group, a heterocyclic
sulfonamido group, an aliphatic sulfinyl group, an arylsulfinyl
group, a nitro group, a nitroso group, a diazo group, an azo group,
a hydrazino group, a di-aliphatic oxyphosphinyl group, a
diaryloxyphosphinyl group, silyl groups (e.g., trimethylsilyl,
t-butyldimethylsilyl, and phenyldimethylsilyl), silyloxy groups
(e.g., trimethylsilyloxy and t-butyldimethylsilyloxy), a borono
group, and ionic hydrophilic groups (e.g., carboxyl, sulfo,
phosphono, and quaternary ammonium group). These substituents may
further have a substituent selected, for example, from the
substituents recited above.
(I) N-Containing Carbon Alloy
[0022] The N-containing carbon alloy of the invention is obtained
by baking an organic material containing an N-containing
crystalline organic compound having a molecular weight of 60 to
2000.
[Nitrogen-Containing Crystalline Organic Compound]
[0023] As used herein, the term "N-containing crystalline organic
compound" means a compound having crystallinity and containing
nitrogen and includes hydrocarbon compounds with a carbon atom of
the hydrocarbon structure replaced with a hetero atom, such as
oxygen, nitrogen, or sulfur, and hydrocarbon compounds with a
hydrogen atom of the hydrocarbon structure replaced with a
functional group containing a hetero atom, such as oxygen,
nitrogen, or sulfur. The N-containing crystalline organic compound
should have crystallinity so that the molecules of the compound may
be regularly oriented with ease. It should be noted, however, that
N-containing metal complexes are excluded from the N-containing
crystalline organic compound because, for one thing, they are
difficult to purify and, for another, the N-containing ligand to
metal complex ratio is fixed so that, when they decompose on
baking, the decomposition rate of the N-containing ligand and the
vaporization rate of the coordinated metal complex cannot be
controlled, presenting difficulties in obtaining an intended
N-containing carbon alloy. Even when an N-containing metal complex
and a low molecular organic compound are mixed, the N-containing
metal complex crystals decompose, and the metal is directly
subjected to reduction. As a result, neighboring metal atoms thus
produced are liable to agglomerate and crystallize. Because the
metal is removed by acid cleaning, the resulting N-containing
carbon alloy is non-uniform only to have reduced functionality. For
use as, for example, a catalyst, the resulting N-containing carbon
alloy will have reduced catalyst activity. For these reasons,
N-containing metal complexes are not suited for use in the
invention.
[Crystal Structure]
[0024] The N-containing crystalline organic compound that can be
used in the invention is selected with considerations given to
.pi.-.pi. interaction, coordinate bond, charge transfer
interaction, and hydrogen bond. It is preferred that the
N-containing crystalline organic compound have a crystal structure
formed by at least two bonds or interactions. By the use of a low
molecular compound having such a crystal structure, the
intermolecular interaction is enhanced, thereby allowing for
control on vaporization during baking in the preparation of an
N-containing carbon alloy.
[0025] As used herein, the term "crystal structure" refers to the
arrangement or alignment of molecules within a crystal. In other
words, a crystal structure is composed of repeated unit cells.
Molecules are located at any position and oriented in the unit cell
and oriented. Molecules assume uniform conformation in a crystal.
That is, because the functional group is uniformly arranged in a
crystal, the intermolecular interaction is equal in and out of the
unit cell. In the case of, for instance, an N-containing
crystalline organic compound having a stacking structure, an
interaction is exerted between aromatic rings, heterocyclic rings,
fused polycyclic structures, fused polyheterocyclic structures, or
unsaturated groups (e.g., C.ident.N, vinyl, allyl, or acetylene).
For example, aromatic rings arranged face to face exert .pi.-.pi.
interaction (often referred to as .pi.-.pi. stacking) The molecules
pile up at regular interval by the intermolecular overlapping of
the sp2 or sp orbitals of carbon atoms of unsaturated bond in these
rings or groups thereby to form stacked columnar assemblies.
[0026] The columnar assemblies have a uniform structure, in which
adjacent columns are arranged with a specific intermolecular
distance by hydrogen bonds or van der Waals forces. This is
advantageous in that heat transfer within crystals is easily
accomplished.
[0027] The N-containing crystalline organic compound used in the
invention is a low molecular compound and yet has crystallinity and
exhibits heat resistance due to vibration relaxation by phonons
(quantized lattice vibration). Therefore, the decomposition
temperature is maintained to the carbonization temperature so that
carbonization is accomplished with reduced vaporization of
decomposition products to form a carbon alloy structure.
[0028] A noncrystalline compound is unfavorable because molecular
orientation is uncontrollable during baking only to provide a
non-uniform structural carbon material.
[0029] It is preferred that the N-containing crystalline organic
compound have a melting temperature of 25.degree. C. or higher. If
the melting temperature is lower than 25.degree. C., there will not
be an air layer during baking, which contributes to heat
resistance, and the compound will boil or bump based on the
temperature vs. vapor pressure relation, resulting in a failure to
obtain a carbon material.
[0030] The N-containing crystalline organic compound for used in
the invention is not particularly limited as long as it is a
crystalline organic compound containing a nitrogen atom and having
a molecular weight of 60 to 2000. The molecular weight of the
N-containing crystalline organic compound is preferably 100 to
1500, more preferably 130 to 1000.
[0031] The N-containing crystalline organic compound preferably has
at least one functional group selected from, for example, the above
mentioned group of substituents and/or a heterocyclic group. In
particular, the N-containing crystalline organic compound
preferably has at least one functional group selected from halogen
(e.g., chlorine, chlorine, bromine, or iodine), hydroxyl, cyano,
aliphatic carbonyl, arylcarbonyl, heterocyclic carbonyl, aliphatic
oxycarbonyl, aryloxycarbonyl, heterocyclic oxycarbonyl, aliphatic
amino, arylamino, heterocyclic amino, acylamino, aliphatic
oxyamino, aryloxyamino, sulfamoylamino, acylsulfamoylamino,
oxamoylamino, aliphatic oxycarbonylamino, aryloxycarbonylamino,
heterocyclic oxycarbonylamino, and carbamoylamino. Examples of the
N-containing crystalline organic compound include amines, imines,
nitriles, imides, and amides. Nitrile compounds, amide compounds
and quinacridone compounds are preferred in terms of crystallinity
and heat resistance, and nitrile compounds and amide compounds are
more preferred.
[0032] The N-containing crystalline organic compound is preferably
an organic compound having an unsaturated bond and at least one
group selected from the group consisting of a nitrile group, an
amido group and 4-quinolone structure in the molecule thereof, more
preferably an organic compound having at least one group selected
from a nitrile group and an amido group and an unsaturated bond in
the molecule thereof, further more preferably an organic compound
having at least one group selected from a nitrile group and an
amido group, at least one group selected from a nitrile group, an
amido group, a halogen atom, and a hydroxyl group, and an
unsaturated bond in the molecule thereof, still further more
preferably an organic compound having at least one group selected
from a nitrile group and an amido group, at least one group
selected from a nitrile group, an amido group, and a halogen atom,
and an unsaturated bond in the molecule thereof.
[0033] It is believed that starting with an N-containing
crystalline organic compound having a nitrile group or an amido
group in its molecule results on baking in the formation of active
sites composed of C, N, and metal atoms having high oxygen
reduction activity in the resulting N-containing carbon alloy.
[0034] It is preferred for the N-containing crystalline organic
compound to have an aromatic ring formed by unsaturated bonds. The
aromatic ring is preferably a heterocyclic ring having one hetero
atom or a benzene ring, with a substituted or unsubstituted benzene
ring and a substituted or unsubstituted pyridine ring being
particularly preferred. The presence of the unsaturated bonds is
considered to induce the above described interaction to form a
carbon alloy skeleton.
[0035] When the molecules of the N-containing crystalline organic
compound have, for example, nitrogen (N) of an amido, amine, or
nitrile group, a hetero atom of a hetero ring (e.g., N of a pyridyl
group), a chalcogen element (e.g., O, S, or Se) of a carbonyl,
ether, or hydroxyl group), or a halogen element (e.g., F, Cl, Br,
or I) between adjacent stacked columns, these atoms form hydrogen
bonds with protons (H.sup.+). Thus, the assembly of the stacked
columns may be controlled by at least one interaction, such as
hydrogen bonds, coordinate bonds, charge transfer interaction,
acid-base interaction, and van der Waals interaction, or by
multiple interaction exerted two-dimensionally or
three-dimensionally in the network.
[0036] The N-containing crystalline organic compounds may be used
either individually or as a mixture of two or more thereof. The
N-containing crystalline organic compound preferably has a metal
content of not more than 10 ppm. The N-containing crystalline
organic compound with the above recited molecular weight is easy to
purify before baking.
[0037] The nitrogen content of the N-containing crystalline organic
compound is preferably 0.1% to 55%, more preferably 1% to 30%, even
more preferably 4% to 20%, by mass. When in using the N-containing
crystalline organic compound with the nitrogen content in that
range, there is no need to separately introduce a
nitrogen-containing compound as a nitrogen source, and nitrogen
atoms and metal atoms are regularly and uniformly arranged along
the crystal edges and allowed to show interaction with each other
easily. As a result, a nitrogen to metal ratio exhibiting higher
oxygen reduction activity will be obtained.
[0038] The N-containing crystalline organic compound is preferably
a volatile-retardant compound having a .DELTA.TG value of -95% to
-0.1%, more preferably -95% to -1%, even more preferably -90% to
-5%, at 400.degree. C. in a nitrogen atmosphere. As will be
described in detail, the N-containing crystalline organic compound
may be mixed with an inorganic metal or an inorganic metal salt as
long as the N-containing crystalline organic compound is capable of
carbonization without vaporization during baking.
[0039] The term ".DELTA.TG" or ".DELTA.TG value" as used herein
denotes a percent mass loss of the organic material, i.e., the
N-containing crystalline organic compound or a mixture of the
N-containing crystalline organic compound and an inorganic metal or
inorganic metal salt, at 400.degree. C. relative to the mass at
room temperature (30.degree. C.) measured by TG-DTA analysis in
which the compound or the mixture is heated from 30.degree. C. to
1000.degree. C. at a rate of temperature rise of 10.degree. C./min,
under flowing nitrogen. The volatile-retardant N-containing
crystalline organic compound having the .DELTA.TG value falling
within the range recited is prevented from decomposing during
baking, which affords an increased carbon yield.
[0040] The N-containing heterocyclic compounds include N-containing
heterocyclic monocyclic compounds and N-containing fused
heterocyclic compounds. Suitable N-containing heterocyclic
monocyclic compounds include 5-membered ring compounds, such as
pyrrole and its derivatives, diazole compounds (e.g., pyrazole and
imidazole) and their derivatives, and triazole compounds and their
derivatives; and 6-membered ring compounds, such as pyridine and
its derivatives, diazine compounds (e.g., pyridazine, pyrimidine,
and pyrazine) and their derivatives, and triazine compounds and
their derivatives (e.g., melamine or cyanuric acid). Suitable
N-containing fused heterocyclic compounds include quinoline,
phenanthroline, and purine.
[0041] Examples of the amines include primary, secondary, and
tertiary amines, diamines, triamines, polyamines, and amino
compounds. The primary to tertiary amines include aliphatic amines,
such as methylamine, ethylamine, dimethylamine, and trimethylamine,
and aromatic amines (e.g., aniline) and derivatives thereof. The
diamines are exemplified by ethylenediamine. The amino compounds
include amino alcohols exemplified by ethanolamine. Examples of the
imines include pyrrolidine and ethyleneimine. Examples of the
nitriles include aliphatic nitriles, such as acetonitrile; aromatic
nitriles and halides thereof, such as benzonitrile, phthalonitrile,
isophthalonitrile, terephthalonitrile, and tetracyanobenzene;
isonitrile; and amino acids. Examples of the amides include
carboxylic acid amides, N-substituted amides, (N-mono- and
disubstituted amides), aromatic amides (aromatic mono- and
diamides), urea, carbamide, urethane, lactam, lactim, hydrazide,
imidic acid, and imidic esters.
[0042] The N-containing heterocyclic compound is preferably a
pigment. Pigments form uniform stacked columnar assemblies via
intermolecular .pi.-.pi. interaction, with the adjacent columns
arranged with a specific intermolecular distance by hydrogen bonds
or van der Waals forces. Therefore, heat transfer within crystals
is easily accomplished. Although the pigments are low molecular
compounds, they have crystallinity and exhibit heat resistance due
to vibration relaxation by phonons (quantized lattice vibration).
Therefore, the decomposition temperature is maintained to the
carbonization temperature so that carbonization is accomplished
with reduced vaporization of decomposition products.
[0043] Preferred pigments are isoindoline pigments, isoindolinone
pigments, diketopyrrolopyrrole pigments, quinacridone pigments,
oxazine pigments, phthalocyanine pigments, quinophthalone pigments,
latent pigments derived from the above described pigments
(described hereinafter), and lake pigments obtained by combining
dyes with a metal ion, with diketopyrrolopyrrole pigments,
quinacridone pigments, isoindoline pigments, isoindolinone
pigments, quinophthalone pigments, latent pigments derived from
these pigments being more preferred. On baking, the pigment
decomposes to form a benzonitrile (Ph-CN) structure, which acts as
a reaction active species to provide a carbon alloy catalyst with
higher oxygen reduction reaction (ORR) activity. When a metal
species (M) is present in the system, the pigment forms a Ph-CN . .
. M complex on baking to provide a carbon alloy with still higher
ORR activity.
[0044] The N-containing crystalline organic compounds include a
compound represented by formula (1) shown below, a tautomer
thereof, or a salt or a hydrate of the compound of formula (1) and
the tautomer.
##STR00001##
[0045] In the formula (1), each of Z.sub.1 and Z.sub.2
independently represents a hydrogen atom, an aliphatic group, an
aryl group, a heterocyclic group, an acyl group, a hydroxyl group,
an aliphatic oxycarbonyl group, a carbamoyl group (--CONH.sub.2),
or a sulfonyl group; n represents an integer 1 to 3; when n=2, the
compound is a dimer formed via Z.sub.1 and Z.sub.2, and when n=3,
the compound is a trimer formed via a benzene or triazine ring
containing Z.sub.1 and Z.sub.2; and A represents any one of the
following formulae (A-1) to (A-39).
##STR00002## ##STR00003## ##STR00004## ##STR00005##
##STR00006##
[0046] In the formulae (A-1) to (A-39), each of R.sub.51, R.sub.52,
R.sub.53, R.sub.54, R.sub.55, R.sub.56, R.sub.57, R.sub.58,
R.sub.59, and R.sub.60 independently represent hydrogen or a
substituent; adjacent substituents may be connected to each other
to form a 5- or 6-membered ring; and the asterisk mark * indicates
the position of the bond to the pyrrolidone structures.
[0047] The aliphatic group as represented by Z.sub.1 and Z.sub.2
may be substituted or unsubstituted and saturated or unsaturated.
The substituent the aliphatic group may have may be any one of
those which are listed above and able to substitute for hydrogen of
the aliphatic group. The aliphatic group is preferably an alkyl
group having 1 to 8 carbon atoms, more preferably alkyl having 1 to
6 carbon atoms, e.g., methyl, ethyl, isopropyl, cyclohexyl, or
t-butyl.
[0048] The aryl group as represented by Z.sub.1 and Z.sub.2 may be
optionally substituted. The substituent the aryl group may have may
be any one of those which are listed above and able to substitute
for hydrogen on the aryl group. The aryl group is preferably an
aryl group having 6 to 12 carbon atoms, more preferably an aryl
group having 6 to 10 carbon atoms, such as phenyl, 3-methoxyphenyl,
or 4-carbamoylphenyl.
[0049] The heterocyclic group as represented by Z.sub.1 and Z.sub.2
may be optionally substituted, saturated or unsaturated, and
monocyclic or a fused ring system. The substituent the heterocyclic
group may have may be any one of those which are listed above and
able to substitute for hydrogen of the heterocyclic group. The
heterocyclic group is preferably a heterocyclic group having 2 to
16 carbon atoms, more preferably a 5- or 6-membered heterocyclic
group having 2 to 12 carbon atoms, such as 1-pyrrolidinyl,
4-morpholinyl, 2-pyridyl, 1-pyrrolyl, 1-imidazolyl, or
1-benzimidazolyl.
[0050] The aliphatic oxycarbonyl group as represented by Z.sub.1
and Z.sub.2 may be optionally substituted and saturated or
unsaturated. The substituent the aliphatic oxycarbonyl group may
have may be any one of those which are listed above and able to
substitute for hydrogen of the aliphatic oxycarbonyl group. The
aliphatic oxycarbonyl group is preferably an alkoxycarbonyl group
having 1 to 8 carbon atoms, more preferably an alkoxycarbonyl group
having 1 to 6 carbon atoms, such as methoxycarbonyl,
ethoxycarbonyl, isopropoxycarbonyl, or
carbamoylmethoxycarbonyl.
[0051] The carbamoyl group as represented by Z.sub.1 and Z.sub.2
may be optionally substituted. The substituent the carbamoyl group
may have may be any one of those which are listed above and able to
substitute for hydrogen of the carbamoyl group and is preferably an
aliphatic group, an aryl group, or a heterocyclic group. The
optionally substituted carbamoyl group is preferably a carbamoyl
group, an alkylcarbamoyl group having 2 to 9 carbon atoms, a
dialkylcarbamoyl group having 3 to 10 carbon atoms, an
arylcarbamoyl group having 7 to 13 carbon atoms, or a heterocyclic
carbamoyl group having 3 to 12 carbon atoms, more preferably a
carbamoyl group, an alkylcarbamoyl group having 2 to 7 carbon
atoms, a dialkylcarbamoyl group having 3 to 6 carbon atoms, an
arylcarbamoyl group having 7 to 11 carbon atoms, or a heterocyclic
carbamoyl group having 3 to 10 carbon atoms, such as carbamoyl,
methylcarbamoyl, dimethylcarbamoyl, phenylcarbamoyl, or
4-pyridinecarbamoyl.
[0052] The sulfamoyl group as represented by Z.sub.1 and Z.sub.2
may be substituted or unsubstituted. The substituent the sulfamoyl
group may have may be any one of those which are listed above and
able to substitute for hydrogen of the sulfamoyl group and is
preferably an aliphatic group, an aryl group, or a heterocyclic
group. The optionally substituted sulfamoyl group is preferably a
sulfamoyl group, an alkylsulfamoyl group having 1 to 9 carbon
atoms, a dialkylsulfamoyl group having 2 to 10 carbon atoms, an
arylsulfamoyl group having 7 to 13 carbon atoms, or a heterocyclic
sulfamoyl group having 2 to 12 carbon atoms, more preferably a
sulfamoyl group, an alkylsulfamoyl group having 1 to 7 carbon
atoms, a dialkylsulfamoyl group having 3 to 6 carbon atoms, an
arylsulfamoyl group having 6 to 11 carbon atoms, or a heterocyclic
sulfamoyl group having 2 to 10 carbon atoms, such as sulfamoyl,
methylsulfamoyl, N,N-dimethylsulfamoyl, phenylsulfamoyl, or
4-pyridinesulfamoyl.
[0053] Z.sub.1 and Z.sub.2 may be connected to each other to form a
5- or 6-membered ring. Examples of the ring formed by Z.sub.1 and
Z.sub.2 include benzene, pyridine, pyrazine, pyrimidine, triazine,
pyridazine, pyrrole, pyrazole, imidazole, triazole, oxazole,
oxadiazole, thiazole, thiadiazole, furan, thiophene, selenophene,
silole, germole, phosphole, and pyrrolidone rings, with
pyrrolidone, benzene, pyridine, pyrazine, pyrimidine, triazine,
pyridazine, pyrrole, pyrazole, imidazole, and triazole rings being
preferred, and with a pyrrolidone ring being more preferred.
[0054] The substituent as R.sub.51 to R.sub.60 may be any of those
listed above and able to substitute for hydrogen as R.sub.51 to
R.sub.60. Suitable substituents as R.sub.51 to R.sub.59 are halogen
(e.g., fluorine, chlorine, bromine, or iodine), aliphatic, aryl,
heterocyclic, hydroxyl, acyl, aliphatic oxycarbonyl, optionally
substituted carbamoyl, acylamino, sulfonamido, aliphatic oxy,
aliphatic thio, cyano, or sulfonyl, preferably halogen (e.g.,
fluorine, chlorine, bromine, or iodine), aliphatic, aryl,
heterocyclic, hydroxyl, aliphatic oxycarbonyl, optionally
substituted carbamoyl, optionally substituted ureido, aliphatic
oxy, or cyano.
[0055] From the viewpoint of effects of the invention, each of
R.sub.51 to R.sub.59 is preferably hydrogen, halogen (e.g.,
fluorine, chlorine, bromine, or iodine), aliphatic, aryl,
heterocyclic, hydroxyl, acyl, aliphatic oxycarbonyl, optionally
substituted carbamoyl, optionally substituted ureido, acylamino,
sulfonamido, aliphatic oxy, aliphatic thio, cyano, or sulfonyl,
more preferably hydrogen, halogen (e.g., fluorine, chlorine,
bromine, or iodine), aliphatic, aliphatic oxycarbonyl, optionally
substituted carbamoyl, optionally substituted ureido, aliphatic
oxy, or cyano.
[0056] The substituent as R.sub.60 may be any of those listed above
and able to substitute for hydrogen as R.sub.60. Preferred
substituents as R.sub.60 are an aliphatic group, an aryl group, a
heterocyclic group, and an aromatic 5- or 6-membered heterocyclic
ring formed through R.sub.60 and the substituent R.sub.51 to
R.sub.59 adjacent to R.sub.60, with an aliphatic group, an aryl
group, a 5- or 6-membered aromatic heterocyclic group having
nitrogen at an ortho position relative to the position of the bond,
and an aromatic 5- or 6-membered heterocyclic ring formed through
R.sub.60 and the substituent R.sub.51 to R.sub.59 adjacent to
R.sub.60 being more preferred.
[0057] In terms of the effects of the invention, R.sub.60 is
preferably an aliphatic group, an aryl group, or a heterocyclic
group, more preferably an aliphatic group, an aryl group, a 5- or
6-membered aromatic heterocyclic group having nitrogen at an ortho
position relative to the position of the bond, or an aromatic 5- or
6-membered heterocyclic ring formed through R.sub.60 and the
substituent R.sub.51 to R.sub.59 adjacent to R.sub.60, even more
preferably a 5- or 6-membered aromatic heterocyclic group having
nitrogen at an ortho position relative to the position of the bond
or an aromatic 5- or 6-membered heterocyclic ring formed through
R.sub.60 and the substituent R.sub.51 to R.sub.59 adjacent to
R.sub.60. When R.sub.60 is a 5- or 6-membered aromatic heterocyclic
group having nitrogen at an ortho position relative to the position
of the bond, not only intermolecular .pi.-.pi. interaction but
intramolecular interaction by hydrogen bonding are exerted to
readily impart heat resistance. When an aromatic 5- or 6-membered
heterocyclic ring formed through R.sub.60 and the substituent
R.sub.51 to R.sub.59 adjacent to R.sub.60 is included, not only
heat resistance is imparted by the intermolecular .pi.-.pi.
interaction, but also nitrogen doping into graphene of carbon alloy
is easily achieved, thereby to provide excellent ORR activity.
[0058] The substituents as R.sub.52, R.sub.53, and R.sub.54 may be
any one of those listed above and able to substitute for hydrogen
on the ring. In terms of the effects of the invention, each of
R.sub.52 to R.sub.54 is preferably a heterocyclic group or an
electron withdrawing group having a Hammett constant .sigma.p of
0.20 or greater, more preferably an electron withdrawing group
having a Hammett constant .sigma.p of 0.30 or greater. The upper
limit of the .sigma.p value is 1.0.
[0059] Examples of the electron withdrawing group with a .sigma.p
value of 0.20 or greater as R.sub.52 to R.sub.54 are an acyl group,
an acyloxy group, a carbamoyl group, an alkyloxycarbonyl group, an
aryloxycarbonyl group, a cyano group, a nitro group, a
dialkylphosphono group, a diarylphosphono group, a diarylphosphinyl
group, an alkylsulfinyl group, an arylsulfinyl group, an
alkylsulfonyl group, an arylsulfonyl group, a sulfonyloxy group, an
acylthio group, a sulfamoyl group, a thiocyanate group, a
thiocarbonyl group, a haloalkyl group, a haloalkoxy group, a
haloaryloxy group, a haloalkylamino group, a haloalkylthio group,
an aryl substituted with another electron withdrawing group having
a .sigma.p value of 0.20 or greater, a heterocyclic group, a
halogen group, an azo group, and a selenocyanate group.
[0060] In the formula (1), A is preferably any one of (A-1) to
(A-16) and (A-39), more preferably any one of (A-1) to (A-4), (A-6)
to (A-8), (A-10), and (A-39).
[0061] On decomposing the compound of formula (1), a CN bond is
formed in the decomposition product because of the cyclic structure
(A-1) to (A-39). The CN bond and a metal interact with each other,
whereby nitrogen is retained until carbonization. As a result,
nitrogen is easily introduced into the graphene layers of carbon
alloy to impart excellent ORR activity. In particular, it is
preferred to use a pigment having such a structural
characteristic.
[0062] Of the heterocyclic structures (A-2) to (A-39), the
N-containing structures (A-2) to (A-4), (A-6) to (A-8), (A-10), and
(A-39) are preferred because nitrogen atoms in the hetero ring will
regularly align along crystal edges originating from the
N-containing crystalline organic compound to allow free metal ions
to coordinate therewith.
[0063] The N-containing crystalline organic compound of the formula
(1) is preferably represented by formula (2).
##STR00007##
[0064] In the formula (2), each of Z.sub.1 and Z.sub.2
independently represent a hydrogen atom, an aliphatic group, an
aryl group, a heterocyclic group, an acyl group, a hydroxyl group,
an aliphatic oxycarbonyl group, a carbamoyl group (--CONH.sub.2),
or a sulfonyl group; n represents an integer 1 to 3; when n=2, the
compound is a C2 symmetric dimer formed via Z.sub.1 and Z.sub.2,
and when n=3, the compound is a C3 symmetric trimer formed via a
benzene ring containing Z.sub.1 and Z.sub.2.
[0065] The preferred types and scopes of Z.sub.1, Z.sub.2, A, and n
in formula (2) are the same as in formula (1).
[0066] The N-containing crystalline organic compound of the formula
(2) is preferably represented by formula (3).
##STR00008##
[0067] In the formula (3), A represents any one of (A-1) to (A-39).
The asterisk mark * indicates the position of the bond to A in the
formula (3).
[0068] The preferred types and scopes of A in the formula (3) are
the same as in the formula (1).
[0069] The N-containing crystalline organic compound of the formula
(1) is preferably represented by the formula (4).
##STR00009##
[0070] In the formula (4), each of Z.sub.1 and Z.sub.2
independently represents a hydrogen atom, an aliphatic group, an
aryl group, a heterocyclic group, an acyl group, a hydroxyl group,
an aliphatic oxycarbonyl group, a carbamoyl group (--CONH.sub.2),
or a sulfonyl group; n represents an integer 1 to 3; when n=2, the
compound is a C2 symmetric dimer formed via Z.sub.1 and Z.sub.2,
and when n=3, the compound is a C3 symmetric trimer formed via a
benzene ring containing Z.sub.1 and Z.sub.2; and R.sub.61,
R.sub.62, R.sub.63, R.sub.64, and R.sub.65 each represent a
hydrogen atom or a substituent; and adjacent substituents may be
connected to each other to form a 5- or 6-membered ring.
[0071] The preferred types and scopes of R.sub.61 to R.sub.65 are
the same as those of R.sub.51 to R.sub.55 in formula (1).
[0072] The N-containing crystalline organic compound of the formula
(3) or (4) is preferably represented by formula (5).
##STR00010##
[0073] In the formula (5), each of R.sub.61, R.sub.62, R.sub.63,
R.sub.64, R.sub.65/R.sub.66, R.sub.67, R.sub.68, R.sub.69, and
R.sub.70 independently represents a hydrogen atom or a substituent,
and adjacent two of the substituents R.sub.61 to R.sub.70 may be
connected to each other to form a 5- or 6-membered ring.
[0074] The preferred types and scopes of R.sub.61 to R.sub.70 in
the formula (5) are the same as those of R.sub.51 to R.sub.55 in
the formula (1).
[0075] The specific examples of the compound represented by the
formula (1) are shown below, but the invention is not restricted to
these compounds.
[0076] In the following specific examples, Me stands for a methyl
group, Bu stands for a butyl group, and Ph stands for a phenyl
group.
##STR00011##
[0077] The pigment that can be used in the invention is not
structurally limited and may be any of magenta, yellow, and cyan
pigments. Suitable organic pigments include perylene pigments,
perynone pigments, quinacridone pigments, quinacridonequinone
pigments, anthraquinone pigments, anthanthrone pigments,
benzimidazolone pigments, disazo condensation pigments, disazo
pigments, azo pigments, indanthrone pigments, indanthrene pigments,
quinophthalone pigments, quinoxalinedione pigments, metal-free
phthalocyanine pigments, triarylcarbonium pigments, dioxazine
pigments, aminoanthraquinone pigments, diketopyrrolopyrrole
pigments, naphthol AS pigments, thioindigo pigments, isoindoline
pigments, isoindolinone pigments, pyranthrone pigments,
isobioranthrone pigments, mixtures of these pigments, latent
pigments derived from these pigments, mixtures of the latent
pigments, and mixtures of the latent pigments and the above
described pigments.
[0078] Examples of suitable pigments include perylene pigments,
such as C.I. Pigment Red 190 (PR190, C.I. No. 71140), C.I. Pigment
Red 224 (PR224, C.I. No. 71127), and C.I. Pigment Violet 29 (PV29,
C.I. No. 71129); perynone pigments, such as C.I. Pigment Orange 43
(PO43, C.I. No. 71105) and C.I. Pigment Red 194 (PR 194, C.I. No.
71100); quinacridone pigments, such as C.I. Pigment Violet 19
(PV19, C.I. No. 73900), C.I. Pigment Violet 42 (PV42), C.I. Pigment
Red 122 (PR122, C.I. No. 73915), C.I. Pigment Red 192 (PR192, C.I.
No. 739155), C.I. Pigment Red 202 (PR202, C.I. No. 73907), C.I.
Pigment Red 207 (PR207, C.I. No. 73900, 73906), and C.I. Pigment
Red 209 (PR209, C.I. No. 73905); quinacridonequinone pigments, such
as C.I. Pigment Red 206 (PR206, C.I. No. 73900/73920), C.I. Pigment
Orange 48 (PO48, C.I. No. 73900/73920), and C.I. Pigment Orange 49
(PO49, C.I. No. 73900/73920); anthraquinone pigments, such as C.I.
Pigment yellow 147 (PY147, C.I. No. 60645); anthanthrone pigments,
such as C.I. Pigment Red 168 (PR168, C.I. No. 59300);
benzimidazolone pigments, such as C.I. Pigment Brown 25 (PB25, C.I.
No. 12510), C.I. Pigment Violet 32 (PV32, C.I. No. 12517), C.I.
Pigment Yellow 180 (PY180, C.I. No. 21290), C.I. Pigment yellow 181
(PY181, C.I. No. 11777), C.I. Pigment Orange 62 (PO62, C.I. No.
11775), and C.I. Pigment Red 185 (PR185, C.I. No. 12516); disazo
condensation pigments, such as C.I. Pigment Yellow 93 (PY93, C.I.
No. 20710), C.I. Pigment yellow 94 (PY94, C.I. No. 20038), C.I.
Pigment Yellow 95 (PY95, C.I. No. 20034), C.I. Pigment yellow 128
(PY128, C.I. No. 20037), C.I. Pigment Yellow 166 (PY166, C.I. No.
20035), C.I. Pigment Orange 34 (PO34, C.I. No. 21115), C.I. Pigment
Orange 13 (P013, C.I. No. 21110), C.I. Pigment Orange 31 (PO31,
C.I. No. 20050), C.I. Pigment Red 144 (PR144, C.I. No. 20735), C.I.
Pigment Red 166 (PR166, C.I. No. 20730), C.I. Pigment Red 220
(PR220, C.I. No. 20055), C.I. Pigment Red 221 (PR221, C.I. No.
20065), C.I. Pigment Red 242 (PR242, C.I. No. 20067), C.I. Pigment
Red 248 (PR248), C.I. Pigment Red 262 (PR262), and C.I. Pigment
Brown 23 (PB23, C.I. No. 20060); disazo pigments, such as C.I.
Pigment yellow 13 (PY13, C.I. No. 21100), C.I. Pigment Yellow 83
(PY83, C.I. No. 21108), and C.I. Pigment Yellow 188 (PY188, C.I.
No. 21094); azo pigments, such as C.I. Pigment Red 187 (PR187, C.I.
No. 12486), C.I. Pigment Red 170 (PR170, C.I. No. 12475), and C.I.
Pigment Yellow 74 (PY74, C.I. No. 11714); indanthrone pigments,
such as C.I. Pigment Blue 60 (PB60, C.I. No. 69800); quinophthalone
pigments, such as C.I. Pigment Yellow 138 (PY138, C.I. No. 56300);
phthalocyanine pigments, such as C.I. Pigment Green 7 (PG7, C.I.
No. 74260), C.I. Pigment Green 36 (PG36, C.I. No. 74265), and
Pigment Blue 16 (PB16, C.I. No. 74100); dioxazine pigments, such as
C.I. Pigment Violet 23 (PV23, C.I. No. 51319) and C.I. Pigment
Violet 37 (PV37, C.I. No. 51345); aminoanthraquinone pigments, such
as C.I. Pigment Red 177 (PR177, C.I. No. 65300);
diketopyrrolopyrrole pigments, such as C.I. Pigment Red 254 (PR254,
C.I. No. 56110), C.I. Pigment Red 255 (PR255, C.I. No. 561050),
C.I. Pigment Red 264 (PR264, C.I. No. 561300), C.I. Pigment Red 272
(PR272, C.I. No. 561150), C.I. Pigment Orange 71 (P071, C.I. No.
561200), and C.I. Pigment Orange 73 (P073); thioindigo pigments,
such as C.I. Pigment Red 88 (PR88, C.I. No. 73312); isoindoline
pigments, such as C.I. Pigment Yellow 139 (PY139, C.I. No. 56298),
C.I. Pigment Yellow 185 (PY185, C.I. No. 12516), C.I. Pigment
Orange 66 (PO66, C.I. No. 48210), and C.I. Pigment Orange 69 (PO69,
C.I. No. 56292); isoindolinone pigments, such as C.I. Pigment
Yellow 109 (PY109, C.I. No. 56284), C.I. Pigment Yellow 110 (PY110,
C.I. No. 56280), C.I. Pigment Yellow 137 (PY137, C.I. No. 561600),
and C.I. Pigment Orange 61 (PO61, C.I. No. 11295); pyranthrone
pigments, such as C.I. Pigment Orange 40 (PO40, C.I. No. 59700) and
C.I. Pigment Red 216 (PO216, C.I. No. 59710); and isobioranthrone
pigments, such as C.I. Pigment Violet 31 (PV31, C.I. No. 60010).
Preferred of them are quinacridone pigments, diketopyrrolopyrrole
pigments, isoindoline pigments, quinophthalone pigments, and latent
pigments derived from these pigments. Particularly preferred
pigments are diketopyrrolopyrrole pigments, such as C.I. Pigment
Red 254 (PR54, C.I. No. 56110), C.I. Pigment Red 255 (PR255, C.I.
No. 561050), C.I. Pigment Red 264 (PR264, C.I. No. 561300), C.I.
Pigment Red 272 (PR272, C.I. No. 561150), C.I. Pigment Orange 71
(P071, C.I. No. 561200), and C.I. Pigment Orange 73 (P073);
quinacridone pigments, such as C.I. Pigment Violet 19 (PV19, C.I.
No. 73900), C.I. Pigment Violet 42 (PC42), C.I. Pigment Red 122
(PR122, C.I. No. 73915), C.I. Pigment Red 192 (PR192, C.I. No.
739155), C.I. Pigment Red 202 (PR202, C.I. No. 73907), C.I. Pigment
Red 207 (PR207, C.I. No. 73900, 73906), and C.I. Pigment Red 209
(PR209, C.I. No. 73905); isoindoline pigments, such as C.I. Pigment
Yellow 139 (PY139, C.I. No. 56298), C.I. Pigment Yellow 185 (PY185,
C.I. No. 12516), C.I. Pigment Orange 66 (PO66, C.I. No. 48210),
C.I. Pigment Orange 69 (PO69, C.I. No. 56292); isoindolinone
pigments, such as C.I. Pigment Yellow 109 (PY109, C.I. No. 56284),
C.I. Pigment Yellow 110 (PY110, C.I. No. 56280), C.I. Pigment
Yellow 137 (PY137, C.I. No. 561600), and C.I. Pigment Orange 61
(PO61, C.I. No. 11295); and quinophthalone pigments, such as C.I.
Pigment Yellow 138 (PY138, C.I. No. 56300).
[0079] Latent pigments derived from the above described pigments
are also useful. The latent pigments may be used individually or as
a mixture of two or more thereof or in combination with the
pigments.
[0080] As used herein, the term "latent pigment" is intended to
mean a compound having a thermally decomposable group and capable
of being easily converted to an organic pigment by applying energy
such as heat. The latent pigment is exemplified by a pigment
compound having introduced to the pigment base thereof a protective
group enhancing solvent solubility. The protective group is easily
released by, for example, chemical, photolytic, or thermal
treatment, whereby the latent pigment is converted to an insoluble
pigment having its essential color. For the details of latent
pigments, reference may be made to Nature, vol. 388, p. 131 (1997).
Examples of suitable latent pigments with various colors and
structures are given, e.g., in JP 9-3362A, WO 98/32802, WO
98/45757, WO 98/58027, WO 99/01511, JP 11-92695A, and JP
11-310726A.
[0081] Latent pigments that are preferably used in the invention
are compound described in the paragraph [0066] and [Chemical
formulae 21 to 27] in JP 2010-83982A. Commercially available latent
pigments may be used as well. Particularly preferred latent
pigments are PR 254-LP and PR 122-LP shown below.
##STR00012##
[0082] The N-containing crystalline organic compounds also include
a compound represented by formula (11) shown below, a tautomer
thereof, or a salt or a hydrate of the compound of the formula (11)
and the tautomer.
NA (11)
[0083] In the formula (11), A represents any one of the formulae
(A-1) to (A-39), in which adjacent two of the substituents R.sub.51
to R.sub.60 may be connected to each other to from a 5- or
6-membered ring or a heterocyclic fused ring system, and the
asterisk mark * indicates the position of the bond to the nitrile
structure in the formula (11).
##STR00013## ##STR00014## ##STR00015## ##STR00016##
##STR00017##
[0084] Preferred types and scopes of the substituents in the cyclic
structures (A-1) to (A-39) are the same as for those in the formula
(1).
[0085] Of the compounds of the formula (11), preferred are those
represented by formulae (13) to (18). In the following specific
examples, Ph represents a phenyl group, t-Bu represents a
tert-butyl group.
##STR00018##
[Inorganic Metal and Inorganic Metal Salt]
[0086] The organic material preferably contains at least one member
selected from an inorganic metal and an inorganic metal salt in
addition to the N-containing crystalline organic compound. In this
preferred embodiment, there can be obtained a carbon alloy
exhibiting higher oxygen reduction activity by the interaction
between nitrogen and metal atoms. That is, the N-containing
crystalline organic compound decomposes on baking, and the
decomposition product forms an N-containing carbon alloy catalyst
in a vapor phase. When metal exists in the vapor phase, the
decomposition product interacts with the metal to form a complex.
The resulting N-containing carbon alloy catalyst thus shows
improved activity.
[0087] The carbon alloy takes the form of fine carbon particles at
least part of which preferably have a turbostratic structure, such
as a nanoshell structure.
[0088] It is more preferred that the carbon alloy of the present
embodiment contains a transition metal or a transition metal
compound. In the more preferred embodiment, the carbon alloy is
produced by carbonizing the N-containing crystalline organic
compound, which contains nitrogen atoms (N) as a constituent
element. It is preferred that, on baking the N-containing
crystalline organic compound, the nitrogen atoms be immobilized on
the surface of the carbon alloy at high concentration by the
catalytic action of the transition metal or transition metal
compound added to the N-containing crystalline organic compound,
thereby forming carbon particles having the nitrogen atoms and the
transition metal or transition metal compound mutually acting on
each other.
[0089] The carbon alloy of the present embodiment exhibits high
activity presumably for the following reason. The N-containing
crystalline organic compound has a uniform structure in which
molecules are stacked into columnar structures by the
intermolecular pi-pi interaction, and the adjacent columns are
arranged with a specific intermolecular distance by hydrogen bonds
or van der Waals forces. The N-containing crystalline organic
compound decomposes and/or vaporizes on heating. Because of being
uniform and crystalline, the compound exhibits excellent heat
transfer. As a result, a high concentration of reaction sites is
provided, and carbon crystals form at many points. In some cases,
interaction occurs with the transition metal or transition metal
compound to catalytically promote carbonization. Therefore, a basic
structure of a carbon alloy is generally a stack of graphene layers
made of sp2-bonded carbon atoms packed in a two-dimensionally
extending honeycomb lattice.
[0090] The carbon alloy of the present embodiment is considered to
be characterized by extremely large number of edge planes.
[0091] The N-containing crystalline organic compound is not
particularly limited in shape as long as the carbon catalyst
activity will be shown. For example, it may be spherical or have a
largely distorted shape, such as elliptic, flattened, or angular.
The form of the N-containing crystalline organic compound may be
sheet-like, fibrous, columnar, or particulate.
[0092] The metal of at least one of the inorganic metal and the
inorganic metal salt is not particularly limited as long as the
carbon catalyst activity is not hindered. Usable metals include di-
to tetra-valent typical metals, transition metals, and inner
transition metals. Examples of the typical metals are Al, Si, Ga,
Ge, As, In, Sn, Sb, Tl, and Pb. Examples of the transition metals
include Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc,
Ru, Rh, Pd, Ag, Cd, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, and Hg.
Examples of the inner transition metals include lanthanides and
actinides, e.g., Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm,
Yb, Lu, Th, Pa, U, Np, and Am.
[0093] Preferred of them are transition metals, particularly those
belonging to the fourth period of Groups 3 to 12 of the Periodic
Table, such as Co, Fe, Mn, Ni, Cu, Ti, V, Cr, Zn, Zr, Nb, Mo, Ta,
and Ce, with Co, Fe, Mn, Ni, Cr, Cu, and Ce being especially
preferred. Co, Fe, Mn) Ni, Cr, Cu, and Ce, and compounds thereof
(such as salts thereof) are competent to form a nanoshell structure
that improves the carbon catalyst activity. Of them, Co and Fe are
particularly superior in forming a nanoshell structure.
Furthermore, Co or Fe incorporated into the carbon catalyst is able
to enhance the oxygen reduction activity of the carbon alloy
catalyst. The most preferred transition metal is Co because a
Co-containing N-containing carbon alloy is superior in storage
stability owing to its non-susceptibility to functional
deterioration due to oxidation with time.
[0094] The carbon alloy may contain one or more element(s) other
than the transition metals, such as boron, alkali metals (e.g., Na,
K, and Cs), alkaline earth metals (e.g., Mg, Ca, and Ba), Pb, Sn,
In, and Tl.
[0095] The inorganic metal salts include, but are not limited to,
hydroxides, oxides, nitrides, sulfates, sulfites, sulfides,
sulfonates, carbonylates, nitrates, nitrites, and halides, with
those having, as a counter ion, a halide ion, a nitrate ion, or a
sulfate ion being preferred. The metal halide, nitrate, or sulfate
having a halide, nitrate, or sulfate counter ion easily allows the
metal element to bond to the surface carbon appearing on thermal
decomposition to increase the specific surface area.
[0096] The inorganic metal salt may contain crystallization water.
The presence of crystallization water of the inorganic metal salt
provides improved thermal conductivity, allowing for uniform
baking. Examples of suitable inorganic metal salts containing
crystallization water are cobalt chloride hydrates, iron (III)
chloride hydrates, and iron (II) chloride hydrates.
[0097] The N-containing carbon alloy of the invention is preferably
obtained by baking an organic material containing 55 to 99.999
parts by mass of the N-containing crystalline organic compound and
0.001 to 45 parts by mass of at least one of an inorganic metal and
an inorganic metal salt, more preferably an organic material
containing 60 to 99.9 parts by mass of the N-containing crystalline
organic compound and 0.1 to 40 parts by mass of at least one of an
inorganic metal, and an inorganic metal salt, even more preferably
an organic material containing 70 to 99 parts by mass of the
N-containing crystalline organic compound and 1 to 30 parts by mass
of at least one of an inorganic metal, and an inorganic metal salt,
each per 100 parts by mass of the total of the N-containing
crystalline organic compound and the inorganic metal and/or the
inorganic metal salt.
[0098] The organic material having the above described preferred
composition provides a carbon alloy with high ORR activity. When
the content of the N-containing crystalline organic compound in the
organic material is less than 55 parts, there are some cases in
which metal atoms vaporized from an inorganic metal or an inorganic
salt gather to form clusters, which further congregate into metal
particles. This is because the ratio of the N-containing
crystalline organic compound to the inorganic metal or inorganic
metal salt is so small that the inorganic metal or inorganic metal
salt are not liable to interact with the decomposition product of
the N-containing crystalline organic compound.
[0099] Metal particles of single nanometer size partly contribute
to the ORR activity whereas those exceeding several tens of
nanometer take no part in the ORR activity.
[0100] While, at this time, the mechanism of the ORR activity is
not entirely clear, the following assumption can be made. The
organic material forms catalytically active sites (metal
coordination sites or spaces formed of or by at least C, N, and a
metal ion) on carbonization, so that oxygen is adsorbed by and
coordinated to the active sites of the catalyst and then
reduced.
[0101] If large metal particles are formed in the step of baking,
the precipitated metal particles will be removed by acid cleaning
after grinding. That is, catalytically active sites (metal
coordination sites or spaces), by and to which oxygen is to be
adsorbed and coordinated, are not formed, resulting in a failure to
exhibit sufficient ORR activity.
[0102] On the other hand, when a metal source and the N-containing
crystalline organic compound are mixed in a ratio within the
recited range, a sufficient amount of the N-containing crystalline
organic compound exists around the individual metal species to
prevent the metal atoms from associating into clusters. Therefore,
an N-containing carbon alloy forms on baking the N-containing
crystalline organic compound, and the metal mildly coordinates to
the N-containing carbon alloy along the edges (where activity will
develop) generated both inside and outside the resulting graphite
to form catalytically active sites. The N-containing carbon alloy
thus exercises its ORR activity sufficiently.
[0103] The ORR activity may be represented by current density
measured by the method described in Examples hereinafter given. To
attain a high output, the current density during oxygen reduction
is preferably as lois possible. Specifically, the current density
is preferably -100 .mu.A/cm.sup.2 or less, more preferably -300
.mu.A/cm.sup.2 or less, even more preferably -1100
.mu.A/cm.sup.2.
[0104] The present embodiment is advantageous in that there is no
need to uniformly disperse the N-containing crystalline organic
compound and the inorganic metal or inorganic metal salt in the
preparation of the organic material to be baked. The mixed state of
the N-containing crystalline organic compound and the inorganic
metal or inorganic metal salt at room temperature is not
influential on the ORR activity of the resulting carbon alloy
because what is necessary to form active species having ORR
activity is believed to be that the decomposition product of the
N-containing crystalline organic compound and vapor of the
inorganic metal salt, etc. should be in contact with each other
during baking.
[0105] The inorganic metal or inorganic metal salt preferably has a
diameter of 0.001 to 100 .mu.m, more preferably 0.01 to 10 .mu.m.
The metallic particles within that size range are able to be
uniformly admixed with the N-containing crystalline organic
compound so that the N-containing crystalline organic compound may
easily form a complex on decomposition. The inorganic metal
particles may have the surface thereof oxidized so long as an
inorganic metal is reproduced during baking.
[0106] The following combinations are exemplified as preferred
embodiments of the present invention.
[0107] Preferred combinations of the metal of at least one of the
inorganic metal and the inorganic metal salt and the N-containing
crystalline organic compound include a combination of iron, cobalt,
iron salt, or cobalt salt and a nitrile compound, an amide
compound, or a quinacridone compound. A more preferred combination
is cobalt, or cobalt salt and an organic compound having at least
one of a nitrile group, an amido group, and 4-quinolone structure
and an unsaturated bond per molecule. An even more preferred
combination is cobalt and an organic compound having at least one
of a nitrile group and an amido group, at least one of a nitrile
group, an amido group, a halogen atom, and a hydroxyl group and an
unsaturated bond in the molecule thereof.
[Carbon Alloy]
[0108] The carbon alloy of the invention, which is obtained by
baking the above described organic material, is an N-containing
carbon alloy having nitrogen doped therein. The carbon alloy of the
invention has a stack of graphene layers made of sp2-bonded carbon
atoms packed in a two-dimensional honeycomb lattice. The carbon
alloys having nitrogen atoms doped into the honeycomb lattice are
divided according to the binding form of nitrogen atom into the
following types (i) through (iv).
(i) Oxide type (N.sub.OX): A nitrogen atom binding to halogen,
oxygen, and so on in an oxidized state. (ii) Graphitic type
(N.sub.Q): A nitrogen atom substituting for one of the carbon atoms
on the boundary between adjacent hexagons of a graphene layer.
(iii) Pyrrolic type (N.sub.5): A nitrogen atom present in an
N-containing pentagon, a result of change from a hexagon of a
graphene layer. (iv) Pyridinic type (N.sub.6): A nitrogen atom
substituting for one carbon atom that is not on the border between
adjacent hexagons of a graphene layer, the carbon atom mostly being
on the edge periphery of a graphene layer (v) Pyridonic type
(N.sub.6*): A nitrogen atom binding to two carbon atoms to make a
hexagon, with one of the carbon atoms having OH or O bonded
thereto.
[0109] The surface nitrogen content and the surface carbon content
of the carbon catalyst are determined by X-ray photoelectron
spectroscopy (XPS). The N.sub.IS XPS spectrum shows peaks at
different binding energies assigned to the difference of the above
defined types of nitrogen atoms. With this feature taken advantage
of, the peaks are separated to compare the intensities, thereby to
obtain the N to C ratio. Typical positions of the peaks of the
nitrogen atoms of the types described are shown below.
(i) N.sub.OX: 402.9.+-.0.2 eV
(ii) N.sub.Q: 401.2.+-.0.2 eV
[0110] (iii) N.sub.5: 400.5.+-.0.2 eV
(iv) N.sub.6: 398.5.+-.0.2 eV
[0111] As stated, there can be pyridonic nitrogen (N.sub.6*) atoms
binding to carbon atoms having an OH group. However, N.sub.6*
nitrogen is not distinguishable from pyrrolic nitrogen (N.sub.5)
because it has an intensity peak at the same binding energy as that
of pyrrolic nitrogen (N.sub.5)(400.5.+-.0.2 eV) (see E.
Raymundo-Pinero et al., Carbon, vol. 40, pp. 597-608 (2002)).
Therefore, in the description of the invention, N.sub.6* nitrogen
atoms are described as being included in "N.sub.5 nitrogen atoms".
Suitability of a nitrogen atom for binding to metal is dependent on
whether the nitrogen atom has an isolated electron pair. A nitrogen
atom having an isolated electron pair donates the electron pair to
the unoccupied orbital of a metal ion to form a coordinate bond. Of
the nitrogen atom types discussed above, N.sub.5 and N.sub.6
nitrogen atoms having an isolated electron pair are effective in
binding to metal, whereas the N.sub.OX and N.sub.Q nitrogen atoms
are not effective. Accordingly, the ratio of the sum of the number
of N.sub.5 nitrogen atoms and the number of N.sub.6 nitrogen atoms
to the total number of nitrogen atoms as obtained by peak
separation of the N.sub.1s XPS spectrum, {(N.sub.5+N.sub.6)/N}, is
preferably 0.2 to 1.0, more preferably 0.3 to 1.0. When
{(N.sub.5+N.sub.6)/N} is smaller than 0.2, the number of nitrogen
atoms capable of binding to metal may be insufficient, which can
result in a failure to obtain sufficient oxygen reduction catalytic
characteristics. The upper limit of {(N.sub.5+N.sub.6)/N} is, in
principle, 1.
[0112] It is more preferred that the carbon alloy catalyst have a
surface nitrogen content to surface carbon content ratio, N/C, of
0.05 to 0.3. When the N to C atomic ratio, N/C, is less than 0.05,
the number of nitrogen atoms capable of binding to metal may be
insufficient, which can result in a failure to obtain sufficient
oxygen reduction catalyzing characteristics. When the N/C exceeds
0.3, the carbon skeleton of the carbon alloy has reduced strength
and reduced electrical conductivity.
[0113] The carbon alloy should be composed of at least carbon atoms
and nitrogen atoms and may contain other atoms, such as hydrogen
and oxygen. In the latter case, the atomic ratio of the other atoms
to the sum of carbon atoms and nitrogen atoms, other atoms/(C+N),
is preferably 0.3 or smaller.
[0114] The specific surface area of the carbon alloy may be
determined by the BET method as follows. A carbon alloy sample is
put in a prescribed container and cooled to the liquid nitrogen
temperature (-196.degree. C.). Nitrogen gas is introduced into the
container to be adsorbed by the carbon alloy. An adsorption
isotherm is prepared, from which a monomolecular adsorption and an
adsorption parameter are calculated. The specific surface area of
the sample is obtained from the results and the known molecular
area of nitrogen (0.162 cm.sup.2).
[0115] The specific surface area, average pore size, and pore
volume of the carbon alloy may be determined by the following
procedures. A carbon alloy sample is put in a prescribed container
and cooled to the liquid nitrogen temperature (-196.degree. C.).
Nitrogen gas is introduced into the container, and the adsorbed
nitrogen quantity is obtained by a volumetric method or a
gravimetric method. The pressure of nitrogen gas introduced is
gradually increased, and the adsorbed gas quantity is plotted
against each equilibrium pressure to obtain a nitrogen adsorption
isotherm. The specific surface area, average pore size, and pore
volume are calculated using the adsorption isotherm in accordance
with the subtracting pore effect (SPE) method (K. Kaneko, et al.,
Carbon, 30, 1075 (1986)). The SPE method is a method to calculate
specific surface area and others by performing micropore analysis
with the use of the .alpha..sub.s-plot method, the t-plot method or
the like and eliminating the effect of strong potential field of
micropores. The SPE method achieves higher accuracy than the BET
method in calculating the specific surface area and the like of a
macroporous sample.
[0116] The pore geometry of the carbon alloy is not particularly
limited. The pores may be only on the surface or not only on the
surface but also inside of the carbon alloy. In the latter case,
the carbon alloy may have pores passing through the carbon alloy
like tunnels or may have spherical or polyhedral (e.g., hexagonal
columnar) voids connected to each other.
[0117] The specific surface area of the carbon alloy is preferably
30 m.sup.2/g or more, more preferably 35 m.sup.2/g or more, even
more preferably 40 m.sup.2/g or more. When the specific surface
area is less than 30 m.sup.2/g, the area capable of being in
contact with a substance to be supported and the number of pores
capable of containing the substance are reduced, thereby, it may be
insufficient to exhibit sufficient oxygen reduction catalytic
characteristics. When the carbon alloy has catalytically active
sites (metal coordination sites or spaces formed of or by at least
C, N, and a metal ion) at a high density, the specific surface area
may be less than 30 m.sup.2/g. It should be noted that, with a
specific surface area of 1000 m.sup.2/g or more, oxygen may fail to
reach the deepest part of the pores, which can result in
insufficient oxygen reduction catalytic characteristics.
[0118] The average pore size of the carbon alloy is preferably 1 to
50 mu, more preferably 2 to 10 nm. When the average pore size is
smaller than 1 nm, the pores are often smaller than a component to
be supported, which can result in a failure to obtain sufficient
ORR catalytic characteristics. When the average pore size is
greater than 50 nm, the specific surface area tends to be
insufficient to exhibit sufficient ORR catalytic
characteristics.
[0119] The pore volume of the carbon alloy is not particularly
limited; for it varies with the specific surface area and the
average pore size. Usually, the pore volume is preferably 0.1 to 50
ml/g, more preferably 0.2 to 2.5 ml/g.
[0120] The form and shape of the carbon alloy are not particularly
limited as long as ORR activity is exhibited. The carbon alloy may
be sheet-like, fibrous, block-like, columar, or particulate and may
have a spherical shape or a largely distorted shape, such as
elliptic, flattened, or angular. Block-like or particulate forms
are preferred in terms of dispersibility.
[0121] The carbon alloy of the invention may be dispersed in a
solvent (disperse medium) to make a slurry. The slurry may be
applied to a substrate, baked, and dried to make a carbon catalyst
of desired shape. By the use of the slurry, a carbon catalyst is
produced with improved processability, which facilitates making an
electrode catalyst of fuel cells or an electrode material of
electrical storage devices.
[0122] The solvent is chosen appropriately from those commonly
employed in the production of electrode catalysts of fuel cells or
electrode materials of electrical storage devices. In producing
electrode materials of electrical storage devices, ordinary polar
solvents, such as diethyl carbonate (DCE), dimethyl carbonate
(DMC), 1,2-dimethoxyethane (DME), ethylene carbonate (EC),
ethylmethyl carbonate (EMC), N-methyl-2-pyrrolidone (NMP),
propylene carbonate (PC), and .gamma.-lactone (GBL), are used
either individually or as a mixture of two or more thereof.
Examples of the solvents used in producing the electrode catalyst
of fuel cells include water, methanol, ethanol, isopropyl alcohol,
butanol, toluene, xylene, methyl ethyl ketone, and acetone.
[0123] In Raman spectrum analysis of the carbon alloy of the
invention, the full width at half maximum of the Raman G-band is
preferably 60 cm.sup.-1 or more, more preferably 70 cm.sup.-1 or
more, even more preferably 80 cm.sup.-1 or more. The carbon alloy
showing such a Raman spectrum has increased edges on its surface to
exhibit improved catalyst activity and shows equal catalyst
activity at any part of it.
(2) Process of Producing N-Containing Carbon Alloy
[0124] The process for producing the N-containing carbon alloy of
the invention includes the steps of (1) mixing an N-containing
crystalline organic compound and an inorganic metal and/or an
inorganic metal salt, (2) raising the temperature of the mixture
from room temperature to a carbonization temperature in an inert
atmosphere at a rate of 1.degree. C./min to 1000.degree. C./min,
(3) maintaining the mixture at a temperature of 500.degree. to
1000.degree. C. for 0.1 to 100 hours, and (4) cooling the mixture
from the carbonization temperature to room temperature.
[0125] The process of the invention is characterized by the step of
heating an organic material containing an N-containing crystalline
organic compound and an inorganic metal and/or an inorganic metal
salt .sigma.p to a carbonization temperature.
[0126] In the step of heating .sigma.p to the carbonization
temperature, the part of the heating operation in which the
temperature is being raised is taken as an infusibilization
treatment.
[0127] The baking temperature for carbonization is not so critical
as long as the N-containing crystalline organic compound undergoes
pyrolysis and carbonization at the temperature. It is preferably
500.degree. to 1000.degree. C., more preferably 550.degree. to
950.degree. C., even more preferably 600.degree. to 900.degree. C.
At reaction temperatures of 500.degree. C. or higher, carbonization
proceeds sufficiently to provide a carbon alloy with high catalyst
performance. At reaction temperatures of 1000.degree. C. or lower,
nitrogen remains in the resulting carbon skeleton to give a desired
N to C atomic ratio securing sufficient ORR activity. At reaction
temperature exceeding 1000.degree. C., nitrogen hardly remains in
the carbon skeleton, tending to result in a reduced atomic N/C and
reduced ORR activity. Furthermore, the yield of the carbonization
product can considerably decrease.
[0128] Carbonization is achieved by maintaining the organic
material at 500.degree. to 1000.degree. C. for 0.1 to 100 hours,
preferably 1 to 10 hours. Extending the carbonizing time over 10
hours tends to result in a failure to obtain merited effects.
[0129] Carbonization is preferably carried out in an inert
atmosphere, for example in a stream of inert gas or non-oxidizing
gas. The gas flow rate is preferably 0.01 to 2.0 more preferably
0.05 to 1.0 l/min, even more preferably 0.1 to 0.5 l/min, per 36 mm
inner diameter. When the flow rate is less than 0.01 l/min,
amorphous carbon by-produced during the baking is not distilled
off, causing reduction of the treating temperature for the
resulting N-containing carbon alloy. When the flow rate is more
than 2.0 l/min, the substrate would vaporize before carbonizing,
resulting in a failure to produce an N-containing carbon alloy. To
obtain a desired N-containing carbon alloy, the above-described
range of gas flow rate is recommended.
[0130] By performing the carbonization at high temperatures in a
single stage, although the carbon alloy yield is reduced, the
resulting carbon alloy has a uniform crystallite size and therefore
has metal atoms uniformly distributed therein and maintains a
highly active state. As a result, a carbon alloy with excellent
oxygen reduction performance is produced.
[0131] The step of raising the temperature may be divided in two
stages. In this case, during the first stage at relatively low
temperatures, thermally instable substances, such as impurities and
the solvent, are removed. Providing a second stage of temperature
rise allows for continuously performing decomposition and
carbonization of the organic material and also causing the
decomposition product and the metal to mutually act to stabilize
the metal in a more active state, for example, to stabilize Fe ions
in a divalent state. As a result, a carbon alloy with excellent
oxygen reduction performance is produced.
[0132] Furthermore, providing the second stage of temperature rise
allows for increasing the treating temperature in the subsequent
carbonization step, thereby to provide a carbon alloy with a
further regulated carbon structure. As a result, the resulting
carbon alloy will have improved conductivity, high oxygen reduction
performance, and improved catalyst life.
[0133] Raising the temperature in the first stage is to preheat the
organic material prior to the second stage while retaining only
thermally stable structures. Raising the temperature in the second
stage .sigma.p to the carbonization temperature is to obtain an
appropriate carbon alloy. If the temperature exceeds the
carbonization temperature at this time, carbonization of the
organic material may proceed excessively, which can result in not
only a failure to obtain an appropriate carbon alloy but also
reduction of yield.
[0134] The first stage temperature rise is preferably carried out
in an inert atmosphere, such as a nitrogen gas atmosphere or a rare
gas atmosphere. The inert gas atmosphere may contain oxygen in such
an amount that does not cause combustion of the organic material.
The inert gas atmosphere may be either in a closed system or in a
semi-closed system with the inert gas flowing therethrough. The
semi-closed system is preferred. In the semi-closed system, the gas
flow rate is preferably 0.01 to 2.0 l/min, more preferably 0.05 to
1.0 l/min, even more preferably 0.1 to 0.5 l/min, per 36 mm inner
diameter.
[0135] In the first stage of temperature rise, the organic material
is preferably heated .sigma.p to a temperature ranging from
100.degree. to 500.degree. C., more preferably 150.degree. to
400.degree. C., to provide a uniformly precarbonized material.
[0136] The first stage of temperature rise may be achieved either
by heating the organic material put in a carbonization chamber from
room temperature to a predetermined temperature or by putting the
organic material in a carbonization chamber previously set at a
predetermined temperature. The former manner is preferred. In the
former case, the temperature is preferably elevated at a constant
rate. More specifically, the rate of temperature rise is preferably
1.degree. C./min to 1000.degree. C./min, more preferably 1.degree.
C. to 500.degree. C./min.
[0137] The second stage of temperature rise may be performed by
continuously raising the temperature of the system from the
temperature of the first stage to the carbonization temperature or
once cooling the system to room temperature followed by raising the
temperature .sigma.p to the carbonization temperature. In the case
where the first stage of temperature rise is once followed by
cooling to room temperature, the cooled precarbonized material may
be uniformly ground to powder, and the powder may be molded into a
desired shape.
[0138] The rate of temperature rise in the second stage is
preferably 10.degree. C./min to 1000.degree. C./min, more
preferably 10.degree. C./min to 500.degree. C./min. The second
stage temperature rise is preferably conducted in an inert
atmosphere. In the case of a semi-closed system with a gas flow,
the inert gas flow rate is preferably 0.01 to 2.0 l/min, more
preferably 0.05 to 1.0 l/min, even more preferably 0.1 to 0.5
l/min, per 36 mm inner diameter. The gas flow rate in the second
stage may be the same or different from that in the first
stage.
[0139] The step of carbonization is preferably carried out in the
presence of an activator. Carbonization at high temperatures in the
presence of an activator results in the formation of a carbon alloy
with developed pores providing an increased surface area. As a
result, the metal on the carbon alloy is exposed, thereby, catalyst
performance is improved. The surface area of the carbonized product
is calculated from a nitrogen gas adsorption.
[0140] Examples of useful activators include, but are not limited
to, at least one selected from the group consisting of carbon
dioxide, water vapor, air, oxygen, alkali metal hydroxides, zinc
chloride, phosphoric acid, and mixtures thereof, with carbon
dioxide, water vapor, air, oxygen, and mixtures thereof being
preferred. A gaseous activator, such as carbon dioxide or water
vapor, is used in a concentration of 2 to 80 mol %, preferably 10
to 60 mol %, in the carbonizing atmosphere. A sufficient activating
effect is obtained with the activator concentrations of 2 mol % or
more. When the activator concentration exceeds 80 mol %, excessive
activation can result in considerable reduction of carbonization
yield, a failure of efficient production of the carbonization
product. A solid activator, such as an alkali metal hydroxide, may
be mixed as such with the precarbonized material or dissolved or
diluted with a solvent, such as water, to make a solution, with
which the carbon alloy precursor is impregnated, or to make a
slurry, which is kneaded into the carbon alloy precursor. A liquid
activator may be diluted with, e.g., water, and the carbon alloy
precursor is impregnated or mixed therewith.
[0141] After completion of the carbonization, the carbon alloy may
be doped with nitrogen. Nitrogen doping may be performed by liquid
phase doping, vapor phase doping, or vapor phase/liquid phase
doping. For example, the carbon alloy is heated in an ammonia gas
atmosphere as a nitrogen source at 200.degree. to 800.degree. C.
for 5 to 180 minutes to introduce nitrogen to the carbon catalyst
surface.
[0142] After the carbonization, the carbon alloy is cooled to room
temperature. After the cooling step, the carbon alloy may be ground
by any method known in the art, for example, by means of a ball
mill.
(3) Applications
[0143] Applications of the N-containing carbon alloy of the
invention include, but are not limited to, structural materials,
electrode materials, filter materials, and catalyst materials. The
N-containing carbon alloy is preferably used as an electrode
material of electrical storage devices, such as capacitors and
lithium secondary batteries. It is more preferably used as a carbon
catalyst of fuel cells, zinc air batteries, and lithium air
batteries featuring high ORR activity. The N-containing carbon
alloy is applicable to a membrane-electrode assembly (MEA) having a
solid polyelectrolyte membrane and catalyst layers adjacent to the
membrane. The carbon catalyst of the N-containing carbon alloy may
be incorporated into the catalyst layers. The MEA may be used in a
fuel cell.
[0144] FIG. 1 is a schematic illustration of a fuel cell 10 having
a carbon catalyst made of the carbon alloy of the invention. The
carbon catalyst is used in the anode and the cathode
electrodes.
[0145] The fuel cell 10 includes a solid polyelectrolyte 14, a pair
of separators 12 and 16, and a pair of electrode catalysts (i.e.,
an anode catalyst (fuel electrode) 13 and a cathode catalyst
(oxidant agent electrode) 15), each pair are facing each other with
the solid polyelectrolyte 14 interposed therebetween. The solid
polyelectrolyte 14 may be a fluorine-based cation exchange resin
membrane typified by a perfluorosulfonic resin membrane. The carbon
catalyst of the invention is disposed in contact with each side of
the solid polyelectrolyte 14 to constitute a fuel cell 10 having
the carbon catalyst as the anode catalyst 13 and the cathode
catalyst 15. The carbon catalyst is formed on each side of the
solid polyelectrolyte 14, and the anode catalyst 13 and the cathode
catalyst 15 are integrated on their electrode reaction layer side
with the respective sides of the solid polyelectrolyte 14 by hot
pressing to make an MEA.
[0146] Conventional fuel cells have a porous sheet as a gas
diffusion layer and as a current collector, such as carbon paper,
disposed between each electrode catalyst and the adjacent
separator. In contrast, the fuel cell 10 of FIG. 1 uses a carbon
catalyst having a large specific surface area and good gas
diffusion properties as an anode catalyst and a cathode catalyst.
By using the above described carbon catalyst as electrode, the
carbon catalyst has a function of gas diffusion when a gas
diffusion layer is not provided, and there can provide a fuel cell
integrated an anode and an cathode electrode catalyst 13 and 15 and
a gas diffusion layer. This achieves size and cost reduction of a
fuel cell.
[0147] The separators 12 and 16 not only support the anode and the
cathode catalyst 13 and 15 but serve supply and exhaust of reactant
gases, such as fuel gas H.sub.2 and oxidizing gas O.sub.2. Upon
supply of the reactant gases to the anode and the cathode
catalysts, a three-phase interface between a vapor phase (reactant
gases), a liquid phase (solid polyelectrolyte membrane), and a
solid phase (catalyst of the electrodes) is formed along the
boundaries between the carbon catalyst of the two electrodes and
the solid polyelectrolyte 14. An electrochemical reaction occurs at
the three-phase interface to generate direct current power. The
electrochemical reactions proceed as follows.
Cathode side: O.sub.2+4H.sup.++4e.sup.-.fwdarw.2H.sub.2O
Anode side: H.sub.2.fwdarw.2H.sup.++2e.sup.-
The H.sup.+ ions generated at the anode move through the solid
polyelectrolyte 14 toward the cathode, while electrons (e.sup.-)
flow through an external load toward the cathode. At the cathode,
on the other hand, water forms as a result of reaction between
oxygen in the oxidizing gas, the H.sup.+ ions coming from the anode
side, and e.sup.-. Thus, the fuel cell generates a direct electric
current from hydrogen and oxygen while forming water.
[0148] An electrical storage device having the carbon catalyst
having the carbon alloy of the invention as an electrode material
will then be described. FIG. 2 schematically illustrates an
electrical double-layer capacitor 20 having the carbon catalyst and
therefore exhibiting high electrical storage capacity.
[0149] The electrical double layer capacitor 20 shown in FIG. 2
includes a pair of polarizable electrodes (a first electrode 21 and
a second electrode 22) separated by a separator 23. These capacitor
components are sealed in a package composed of a case 24b and a cap
24a. The first electrode 21 and the second electrode 22 are
connected to the cap 24a and the case 24b, respectively, via
respective current collectors 25. The separator 23 is impregnated
with an electrolyte. The cap 24a and the case 24b are swaged to
each other via a gasket 26 for electrical insulation
therebetween.
[0150] The carbon catalyst of the invention is applied to the first
electrode 21 and the second electrode 22 to complete an electrical
double layer capacitor having the carbon catalyst as electrode
material. The carbon catalyst described has a fibrous structure
formed of nanoshell carbon particles. The fibers are of nanometer
diameter to provide a large specific surface area, thereby
providing a large electrode interface where electrical charges are
stored in the capacitor. The carbon catalyst is electrochemically
inert to the electrolyte and has appropriate electrical
conductivity. Therefore, applying the carbon catalyst to the
electrodes of capacitors brings about improvement in electrostatic
capacity per electrode unit volume.
[0151] Similarly to the application to the capacitor, the carbon
catalyst of the invention is also applicable as an electrode
material formed of a carbon material, such as a negative electrode
material of lithium ion secondary batteries. Having a large
specific surface area, the carbon catalyst provides a secondary
battery with a large storage capacity.
[0152] An embodiment of application of the carbon alloy of the
invention as a substitute for a noble metal-based (e.g., Pt-based)
environmental catalyst will now be described.
[0153] An environmental catalyst having a catalyst material
containing a noble metal-based (e.g., Pt-based) material or a
composite thereof has been used as a catalyst for exhaust gas
purification, which is to remove contaminants (chiefly gaseous
substances) from contaminated air by decomposition or otherwise.
The above described carbon catalyst is useful as a substitute for
this type of catalyst. The carbon catalyst has a function to
decompose substances to be removed, such as contaminants, because
of its ORR catalyzing action. Accordingly, an environmental
catalyst is provided at a lower cost by using the carbon catalyst
in place of expensive noble metals such as platinum. Furthermore,
having a large specific surface area, the carbon catalyst has an
increased area capable of decomposing substances to be removed per
unit volume, thereby providing an environmental catalyst with
excellent decomposing function per unit volume.
[0154] The carbon catalyst may also be used as a catalyst carrier
on which a noble metal-based (e.g., Pt-based) material used in
conventional environmental catalysts is supported either alone or
in the form of a composite thereof, thereby establishing an
environmental catalyst with improved catalyst activity, such as
decomposing activity. The environmental catalyst having the carbon
catalyst is useful not only as a catalyst for exhaust gas
purification as described but also as a catalyst for purifying
water.
[0155] The carbon alloy of the invention is also useful as a
catalyst for a wide range of chemical reactions, especially as a
substitute for platinum catalysts. That is, the above described
carbon catalyst is useful as a substitute for general processing
catalysts containing a noble metal, e.g., platinum, in chemical
industries. Without using expensive noble metals, such as platinum,
the carbon alloy provides low-cost catalysts for chemical reaction
processes. Having a large specific surface area, the carbon
catalyst provides a catalyst for chemical reaction processes with
excellent chemical reaction efficiency per unit volume.
[0156] Examples of the carbon catalysts for chemical reactions
include catalysts for hydrogenation, catalysts for dehydrogenation,
catalysts for oxidation, catalysts for polymerization, catalysts
for reforming reaction, and catalysts for steam reforming. More
specifically, the carbon catalyst is applicable to various chemical
reactions with reference to the literature relating to catalysts,
such as T. Shirosaki & N. Tohdo, SHOKUBAI CYOSEI, Kodansha,
1975.
[0157] The present invention will now be illustrated in greater
detail with reference to Examples, but it should be understood that
the invention is not deemed to be limited thereto.
Example 1
Synthesis of Carbon Material (1C) from PR 254
(1) Infusibilization and Carbonization
[0158] Pigment Red 254 (from Tokyo Chemical Industry Co., Ltd.;
hereinafter "PR 254") (1.001 g) is weighed into a quartz boat. The
quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The PR 254 is heated at a rate of
temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
800.degree. C., maintained at 800.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.346 g of a
carbon material (1B).
(2) Grinding
[0159] The carbon material (1B) is ground in an agate mortar to
obtain a carbon material (1C).
##STR00019##
Molecular formula: C.sub.18H.sub.10Cl.sub.2N.sub.2O.sub.2 Molecular
weight: 357.190 Elemental analysis (calcd.): C, 60.53; H, 2.82; Cl,
19.85; N, 7.84; O, 8.96.
Comparative Example 1
Synthesis of Carbon Material (C1C) from PhOH
Infusibilization and Carbonization
[0160] Phenol (PhOH) (from Wako Pure Chemical Industries, Ltd.)
(1.000 g) is weighed into a quartz boat. The quartz boat is placed
in the middle of a quartz tube (outer diameter: 4.0 cm; inner
diameter: 3.6 cm) inserted in a tubular furnace. Nitrogen is made
to flow at a rate of 300 ml/min for 30 minutes at room temperature.
The PhOH is heated at a rate of temperature rise of 1.degree.
C./min from 30.degree. C. to 300.degree. C. and then at 10.degree.
C./min from 300.degree. C. to 700.degree. C., maintained at
700.degree. C. for 1 hour, and cooled to room temperature over a
period of 3 hours, resulting in a failure to obtain a carbon
material.
[0161] The same procedures are repeated, except for replacing
phenol with phthalonitrile (from Wako Pure Chemical Industries,
Ltd.), resulting in the same failure.
Phenol:
[0162] Molecular formula: C.sub.6H.sub.6O Molecular weight: 94.11
Elemental analysis (calcd.): C, 76.57; H, 6.43; N, 0.00; O,
17.00.
Phthalonitrile:
[0163] Molecular formula: C.sub.8H.sub.4N.sub.2 Molecular weight:
128.13 Elemental analysis (calcd.): C, 74.99; H, 3.15; N,
21.86.
Comparative Example 2
Synthesis of Carbon Material (C2C) from MeCN
Infusibilization and Carbonization
[0164] Acetonitrile (MeCN) (from Wako Pure Chemical Industries,
Ltd.) (1.000 g) is weighed into a quartz boat. The quartz boat is
placed in the middle of a quartz tube (outer diameter: 4.0 cm;
inner diameter: 3.6 cm) inserted in a tubular furnace. Nitrogen is
made to flow at a rate of 300 ml/min for 30 minutes at room
temperature. The MeCN is heated at a rate of temperature rise of
1.degree. C./min from 30.degree. C. to 300.degree. C. and then at
10.degree. C./min from 300.degree. C. to 700.degree. C., maintained
at 700.degree. C. for 1 hour, and cooled to room temperature over a
period of 3 hours, resulting in a failure to obtain a carbon
material.
Acetonitrile:
[0165] Molecular formula: C.sub.2H.sub.3N Molecular weight: 41.05
Elemental analysis (calcd.): C, 58.51; H, 7.37; N, 34.12.
Example 2
Synthesis of Carbon Material (2C) from Iron (III) Chloride
Hexahydrate/PR 202 Mixture
(1) Preparation of Iron (III) Chloride Hexahydrate/PR 202
Mixture
[0166] To 4.0 g of 2,9-dichloroquinacridone (CINQUASIA Magenta P,
from BASF Japan Ltd.) (hereinafter PR 202) is added 1.017 g of iron
(III) chloride hexahydrate (from Wako Pure Chemical Industries,
Ltd.) and mixed in an agate mortar to prepare an iron (III)
chloride hexahydrate/PR 202 mixture (2A).
(2) Infusibilization and Carbonization
[0167] The mixture (2A) (1.002 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (2A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.529 g of a
carbon material (2B).
(3) Grinding and Acid Cleaning
[0168] The carbon material (2B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (2C).
##STR00020##
Molecular formula: C.sub.20H.sub.10Cl.sub.2N.sub.2O.sub.2 Molecular
weight: 381.212 Elemental analysis (calcd.): C, 63.01; H, 2.64; Cl,
18.60; N, 7.35; O, 8.39.
Example 3
Synthesis of Carbon Material (3C) from Iron (III) Chloride
Hexahydrate/PO 71 Mixture
(1) Preparation of Iron (III) Chloride Hexahydrate/PO 71
Mixture
[0169] To 4.0 g of Pigment Orange 71 (CROMOPHTAL DPP ORANGE TR from
BASF Japan Ltd.) (hereinafter PO 71) is added 1.065 g of iron (III)
chloride hexahydrate (Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare an iron (III) chloride
hexahydrate/PO 71 mixture (3A).
(2) Infusibilization and Carbonization
[0170] The mixture (3A) (1.006 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (3A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.390 g
of a carbon material (3B).
(3) Grinding and Acid Cleaning
[0171] The carbon material (3B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (3C).
##STR00021##
Molecular formula: C.sub.20H.sub.10N.sub.4O.sub.2 Molecular weight:
338.319 Elemental analysis (calcd.): C, 71.00; H, 2.98; N, 16.56;
O, 9.46.
Example 4
Synthesis of Carbon Material (4C) from Iron (III) Chloride/PR 254
Mixture
(1) Preparation of Iron (III) Chloride/PR 254 Mixture
[0172] To 4.0 g of PR 254 (IRGAPHOR RED BT-CF, from BASF Japan
Ltd.) is added 0.606 g of iron (III) chloride (from Wako Pure
Chemical Industries, Ltd.) and mixed in an agate mortar to prepare
an iron (III) chloride/PR 254 mixture (4A).
(2) Infusibilization and Carbonization
[0173] The mixture (4A) (1.003 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (4A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.372 g of a
carbon material (4B).
(3) Grinding and Acid Cleaning
[0174] The carbon material (4B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (4C).
Example 5
Synthesis of Carbon Material (5C) from Iron (III) Chloride
Hexahydrate/PR 254 Mixture
(1) Preparation of Iron (III) Chloride Hexahydrate/PR 254
Mixture
[0175] To 3.00 g of PR 254 (IRGAPHOR RED BT-CF, from BASF Japan
Ltd.) is added 1.614 g of iron (III) chloride hexahydrate (from
Wako Pure Chemical Industries, Ltd.) and mixed in an agate mortar
to prepare an iron (III) chloride hexahydrate/PR 254 mixture
(5A).
(2) Infusibilization and Carbonization
[0176] The mixture (5A) (1.010 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (5A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
800.degree. C., maintained at 800.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.341 g of a
carbon material (5B).
(3) Grinding and Acid Cleaning
[0177] The carbon material (5B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (5C).
Example 6
Synthesis of Carbon Material (6C) from Iron (III) Chloride
Hexahydrate/PR 254 Latent Pigment Mixture
(1) Preparation of Iron (III) Chloride Hexahydrate/PR 254 Latent
Pigment Mixture
[0178] Iron (III) chloride hexahydrate (from Wako Pure Chemical
Industries, Ltd.) (0.544 g) is added to 4.00 g of a PR 254 latent
pigment, which is compound (12) shown in JP 2010-83982A, para.
[0072] (hereinafter "PR 254-LP") and mixed in an agate mortar to
prepare an iron (III) chloride hexahydrate/PR 254-LP mixture
(6A).
(2) Infusibilization and Carbonization
[0179] The mixture (6A) (1.013 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (6A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.259 g
of a carbon material (6B).
(3) Grinding and Acid Cleaning
[0180] The carbon material (6B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (6C).
##STR00022##
Molecular formula: C.sub.28H.sub.30O.sub.2N.sub.2O.sub.2 Molecular
weight: 497.456 Elemental analysis (calcd.): C, 67.60; H, 6.08; Cl,
14.25; N, 5.63; O, 6.43.
Example 7
Synthesis of Carbon Material (7C) from Iron (III) Chloride
Hexahydrate/PR 254 Mixture
(1) Preparation of Iron (III) Chloride Hexahydrate/PR 254
Mixture
[0181] To 3.0 g of PR 254 (IRGAPHOR RED BT-CF, from BASF Japan
Ltd.) is added 0.757 g of iron (III) chloride hexahydrate (from
Wako Pure Chemical Industries, Ltd.) and mixed in an agate mortar
to prepare an Iron (III) Chloride Hexahydrate/PR 254 mixture
(7A).
(2) Infusibilization and Carbonization
[0182] The mixture (7A) (1.003 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (7A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.372 g
of a carbon material (7B).
(3) Grinding and Acid Cleaning
[0183] The carbon material (7B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (7C).
Example 8
Synthesis of Carbon Material (8C) from Iron (II) Chloride
Tetrahydrate/PR 254 Mixture
[0184] (1) Preparation of Iron (II) Chloride Tetrahydrate/PR 254
mixture
[0185] To 4.0 g of PR 254 (IRGAPHOR RED BT-CF, from BASF Japan
Ltd.) is added 0.742 g of iron (II) chloride tetrahydrate (from
Wako Pure Chemical Industries, Ltd.) and mixed in an agate mortar
to prepare an iron (II) chloride tetrahydrate/PR 254 mixture
(8A).
(2) Infusibilization and Carbonization
[0186] The mixture (8A) (1.005 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (8A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.390 g of a
carbon material (8B).
(3) Grinding and Acid Cleaning
[0187] The carbon material (8B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (8C).
Example 9
Synthesis of Carbon Material (9C) from Iron (III) Chloride
Hexahydrate/4,5-Dichlorophthalonitrile (DCP) Mixture
(1) Preparation of Iron (III) Chloride Hexahydrate/DCP Mixture
[0188] To 5.04 g of 4,5-dichlorophthalonitrile (DCP) (from Tokyo
Chemical Industry Co., Ltd.) is added 1.15 g of iron (III) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare an iron (III) chloride hexahydrate/DCP
mixture (9A).
(2) Infusibilization and Carbonization
[0189] The mixture (9A) (1.022 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (9A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.250 g
of a carbon material (9B).
(3) Grinding and Acid Cleaning
[0190] The carbon material (9B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (9C).
4,5-Dichlorophthalonitrile
[0191] Molecular formula: C.sub.8H.sub.2N.sub.2Cl.sub.2 Molecular
weight: 197.02 Elemental analysis (calcd.): C, 48.77; H, 1.02; N,
14.22; Cl, 35.99.
Comparative Example 3
Synthesis of Carbon Material (C3C) from Iron Phthalocyanine
(Fe-Pc)
(1) Infusibilization and Carbonization
[0192] Iron phthalocyanine (Fe-Pc) (from Tokyo Chemical Industry
Co., Ltd.) (1.007 g) is weighed into a quartz boat. The quartz boat
is placed in the middle of a quartz tube (outer diameter: 4.0 cm;
inner diameter: 3.6 cm) inserted in a tubular furnace. Nitrogen is
made to flow at a rate of 300 ml/min for 30 minutes at room
temperature. The Fe-Pc is heated at a rate of temperature rise of
1.degree. C./min from 30.degree. C. to 300.degree. C. and then at
10.degree. C./min from 300.degree. C. to 700.degree. C., maintained
at 700.degree. C. for 1 hour, and cooled to room temperature over a
period of 3 hours to obtain 0.684 g of a carbon material (C3B).
(2) Grinding and Acid Cleaning
[0193] The carbon material (C3B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (C3C).
##STR00023##
Molecular formula: C.sub.32H.sub.16FeN.sub.8 Molecular weight:
568.368 Elemental analysis (calcd.): C, 67.62; H, 2.84; Fe, 9.83;
N, 19.71.
Example 10
Synthesis of Carbon Material (10C) from Cobalt (II) Chloride
Hexahydrate/4,5-Dichlorophthalonitrile (DCP) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/DCP Mixture
[0194] To 4.00 g of 4,5-dichlorophthalonitrile (DCP) (from Tokyo
Chemical Industry Co., Ltd.) is added 0.805 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/DCP mixture (10A).
(2) Infusibilization and Carbonization
[0195] The mixture (10A) (1.032 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (10A) is heated at a rate
of temperature rise of 5.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.323 g of a
carbon material (10B).
(3) Grinding and Acid Cleaning
[0196] The carbon material (10B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (10C).
Example 11
Synthesis of Carbon Material (11C) from Cobalt (II) Chloride
Hexahydrate/PR 122 Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PR 122
Mixture
[0197] To 4.0 g of 2,9-dimethylquinacridone (Chromophtal Pink PT,
from BASF Japan Ltd.) (hereinafter PR 122) is added 1.016 g of
cobalt (II) chloride hexahydrate (from Wako Pure Chemical
Industries, Ltd.) and mixed in an agate mortar to prepare a cobalt
(II) chloride hexahydrate/PR 122 mixture (11A).
(2) Infusibilization and Carbonization
[0198] The mixture (11A) (1.003 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (11A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.670 g of a
carbon material (11B).
(3) Grinding and Acid Cleaning
[0199] The carbon material (11B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (11C).
##STR00024##
Molecular formula: C.sub.22H.sub.16N.sub.2O.sub.2 Molecular weight:
340.375 Elemental analysis (calcd.): C, 77.63; H, 4.74; N, 8.23; O,
9.40.
Example 12
Synthesis of Carbon Material (12C) from Cobalt (II) Chloride
Hexahydrate/4-Hydroxyphthalonitrile (4-HPN) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/4-HPN
Mixture
[0200] To 4.26 g of 4-hydroxyphthalonitrile (4-HPN) (from Tokyo
Chemical Industry Co., Ltd.) is added 1.10 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/4-HPN mixture (12A).
(2) Infusibilization and Carbonization
[0201] The mixture (12A) (1.003 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (12A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.503 g
of a carbon material (12B).
(3) Grinding and Acid Cleaning
[0202] The carbon material (12B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (12C).
4-Hydroxyphthalonitrile
[0203] Molecular formula: C.sub.8H.sub.4N.sub.2O Molecular weight:
144.13 Elemental analysis (calcd.): C, 66.67; H, 2.80; N, 19.44; O,
11.10.
Example 13
Synthesis of Carbon Material (13C) from Cobalt (II) Chloride
Hexahydrate/4,5-Dihydroxybenzonitrile (4,5-DHBN) Mixture
[0204] (1) Preparation of cobalt (II) chloride hexahydrate/4,5-DHBN
mixture
[0205] To 5.0 g of 4,5-dihydroxybenzonitrile (4,5-DHBN) (from Wako
Pure Chemical Industries, Ltd.) is added 1.47 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/4,5-DHBN mixture (13A).
(2) Infusibilization and Carbonization
[0206] The mixture (13A) (1.008 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (13A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.174 g
of a carbon material (13B).
(3) Grinding and Acid Cleaning
[0207] The carbon material (13B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (13C).
4,5-Dihydroxybenzonitrile
[0208] Molecular formula: C.sub.7H.sub.5NO.sub.2 Molecular weight:
135.12 Elemental analysis (calcd.): C, 62.22; H, 3.73; N, 10.37; O,
23.37.
Example 14
Synthesis of Carbon Material (14C) from Cobalt (II) Chloride
Hexahydrate/Phthalonitrile (PN) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PN Mixture
[0209] To 4.00 g of phthalonitrile (PN) (from Tokyo Chemical
Industry Co., Ltd.) is added 1.24 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride hexahydrate/PN
mixture (14A).
(2) Infusibilization and Carbonization
[0210] The mixture (14A) (1.002 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (14A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.092 g
of a carbon material (14B).
(3) Grinding and Acid Cleaning
[0211] The carbon material (14B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (14C).
Phthalonitrile:
[0212] Molecular formula: C.sub.8H.sub.4N.sub.2 Molecular weight:
128.13 Elemental analysis (calcd.): C, 74.99; H, 3.15; N,
21.86.
Example 15
Synthesis of Carbon Material (15C) from Cobalt (II) Chloride
Hexahydrate/Vulcan Black (VB)/PN Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/VB/PN
Mixture
[0213] To 4.00 g of phthalonitrile (PN) (from Tokyo Chemical
Industry Co., Ltd.) is added 1.24 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar. To 2.00 g of the resulting mixture is further
added 2.00 g of Vulcan Black (VB) (XC-72, from Cabot Corporation)
to prepare a cobalt (II) chloride hexahydrate/VB/PN mixture
(15A).
(2) Infusibilization and Carbonization
[0214] The mixture (15A) (1.004 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (15A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.546 g
of a carbon material (15B).
(3) Grinding and Acid Cleaning
[0215] The carbon material (15B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (15C).
Example 16
Synthesis of Carbon Material (16C) from Cobalt (II) Chloride
Hexahydrate/VB/4-Hydroxyphthalonitrile (4-HPN) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/VB/4-HPN
Mixture
[0216] To 4.26 g of 4-hydroxyphthalonitrile (4-HPN) (from Tokyo
Chemical Industry Co., Ltd.) is added 1.10 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar. To 2.00 g of the resulting mixture is
further added 2.00 g of Vulcan Black (VB) (XC-72, from Cabot) to
prepare a cobalt (II) chloride hexahydrate/VB/4-HPN mixture
(16A).
(2) Infusibilization and Carbonization
[0217] The mixture (16A) (1.004 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (16A) is heated at a rate
of temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.667 g of a
carbon material (16B).
(3) Grinding and Acid Cleaning
[0218] The carbon material (16B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (16C).
Example 17
Synthesis of Carbon Material (17C) from Cobalt (II) Chloride
Hexahydrate/Malononitrile (MN) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/MN Mixture
[0219] To 5.00 g of malononitrile (MN) (from Wako Pure Chemical
Industries, Ltd.) is added 3.00 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride hexahydrate/MN
mixture (17A).
(2) Infusibilization and Carbonization
[0220] The mixture (17A) (1.042 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (17A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.239 g
of a carbon material (17B).
(3) Grinding and Acid Cleaning
[0221] The carbon material (17B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (17C).
Malononitrile:
[0222] Molecular formula: C.sub.3H.sub.2N.sub.2 Molecular weight:
66.06 Elemental analysis (calcd.): C, 54.54; H, 3.05; N, 42.41.
Example 18
Synthesis of Carbon Material (18C) from Cobalt (II) Chloride
Hexahydrate/2-Cyanobenzamide (2-CBA) Mixture
[0223] (1) Preparation of cobalt (II) chloride hexahydrate/2-CBA
mixture
[0224] To 5.13 g of 2-cyanobenzamide (2-CBA) (from Tokyo Chemical
Industry Co., Ltd.) is added 1.39 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride hexahydrate/2-CBA
mixture (18A).
(2) Infusibilization and Carbonization
[0225] The mixture (18A) (1.023 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (18A) is heated at a rate
of temperature rise of 5.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.260 g
of a carbon material (18B).
(3) Grinding and Acid Cleaning
[0226] The carbon material (18B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (18C).
2-Cyanobenzamide
[0227] Molecular formula: C.sub.8H.sub.6N.sub.2O Molecular weight:
66.06 Elemental analysis (calcd.): C, 65.75; H, 4.14; N, 19.17; O,
10.95.
Example 19
Synthesis of Carbon Material (19C) from Cobalt (II) Chloride
Hexahydrate/3-Cyanobenzamide (3-CBA) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/3-CBA
Mixture
[0228] To 4.00 g of 3-cyanobenzamide (3-CBA) (compound 16a shown in
J. Chem. Soc., Perkin Trans. I. 13, 1679 (1994)) is added 1.085 g
of cobalt (II) chloride hexahydrate (from Wako Pure Chemical
Industries, Ltd.) and mixed in an agate mortar to prepare a cobalt
(II) chloride hexahydrate/3-CBA mixture (19A).
(2) Infusibilization and Carbonization
[0229] The mixture (19A) (1.003 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (19A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.075 g
of a carbon material (19B).
(3) Grinding and Acid Cleaning
[0230] The carbon material (19B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (19C).
3-Cyanobenzamide
[0231] Molecular formula: C.sub.8H.sub.6N.sub.2O Molecular weight:
66.06 Elemental analysis (calcd.): C, 65.75; H, 4.14; N, 19.17; O,
10.95.
Example 20
Synthesis of Carbon Material (20C) from Cobalt (II) Chloride
Hexahydrate/4-Chloronitrobenzonitrile (Cl-Ph-CN) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/Cl-Ph-CN
Mixture
[0232] To 4.0 g of 4-chloronitrobenzonitrile (Cl-Ph-CN) (from Tokyo
Chemical Industry Co., Ltd.) is added 1.15 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/Cl-Ph-CN mixture (20A).
(2) Infusibilization and Carbonization
[0233] The mixture (20A) (1.012 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (20A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.0526 g
of a carbon material (20B).
(3) Grinding and Acid Cleaning
[0234] The carbon material (20B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (20C).
4-Chloronitrobenzonitrile
[0235] Molecular formula: C.sub.7H.sub.4C1 Molecular weight: 137.57
Elemental analysis (calcd.): C, 61.12; H, 2.93; N, 10.18; Cl,
25.77.
Example 21
Synthesis of Carbon Material (21C) from Cobalt (II) Chloride
Hexahydrate/Ketjen Black (KB)/Cl-Ph-CN Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/Kb/Cl-Ph-CN
Mixture
[0236] To 4.0 g of 4-chloronitrobenzonitrile (Cl-Ph-CN) (from Tokyo
Chemical Industry Co., Ltd.) is added 1.15 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar. To 2.0 g of the resulting mixture is
further added 2.0 g of Ketjen black (KB) (EC300J, from Lion Corp.)
to prepare a cobalt (II) chloride hexahydrate/KB/Cl-Ph-CN mixture
(21A).
(2) Infusibilization and Carbonization
[0237] The mixture (21A) (0.514 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (21A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.292 g
of a carbon material (21B).
(3) Grinding and Acid Cleaning
[0238] The carbon material (21B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (21C).
Example 22
Synthesis of Carbon Material (22C) from Cobalt (II) Chloride
Hexahydrate/VB/DCP Mixture
[0239] (1) Preparation of cobalt (II) chloride hexahydrate/VB/DCP
mixture
[0240] To 4.00 g of 4,5-dichlorophthalonitrile (DCP) (from Tokyo
Chemical Industry Co., Ltd.) is added 0.805 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar. To 2.0 g of the resulting mixture is
further added 2.0 g of Vulcan Black (VB) (XC-72, from Cabot
Corporation) to prepare a cobalt (II) chloride hexahydrate/VB/DCP
mixture (22A).
(2) Infusibilization and Carbonization
[0241] The mixture (22A) (1.003 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (22A) is heated at a rate
of temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.632 g
of a carbon material (22B).
(3) Grinding and Acid Cleaning
[0242] The carbon material (22B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (22C).
Example 23
Synthesis of Carbon Material (23C) from Cobalt Chloride (II)
Hexahydrate/PR 254 Latent Pigment (PR 254-LP) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PR 254-LP
Mixture
[0243] Cobalt (II) chloride hexahydrate (from Wako Pure Chemical
Industries, Ltd.) (0.479 g) is added to 4.00 g of PR 254 latent
pigment (PR 254-LP), which is compound (12) shown in [chemical
formula 24] of para. [0072] and [chemical formula 17] of para.
[0158] in JP 2010-83982A, and mixed in an agate mortar to prepare a
cobalt (II) chloride hexahydrate/PR 254-LP mixture (23A).
(2) Infusibilization and Carbonization
[0244] The mixture (23A) (0.996 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (23A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.270 g of a
carbon material (23B).
(3) Grinding and Acid Cleaning
[0245] The carbon material (23B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (23C).
Example 24
Synthesis of Carbon Material (24C) from Cobalt (II) Nitrate
Hexahydrate/PR 254 Mixture
(1) Preparation of Cobalt (II) Nitrate Hexahydrate/PR 254
Mixture
[0246] To 4.0 g of PR 254 (IRGAPHOR RED BT-CF, from BASF Japan
Ltd.) is added 1.09 g of cobalt (II) nitrate hexahydrate (from Wako
Pure Chemical Industries, Ltd.) and mixed in an agate mortar to
prepare a cobalt (II) nitrate hexahydrate/PR 254 mixture (24A).
(2) Infusibilization and Carbonization
[0247] The mixture (24A) (1.004 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (24A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.366 g of a
carbon material (24B).
(3) Grinding and Acid Cleaning
[0248] The carbon material (24B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (24C).
Example 25
Synthesis of Carbon Material (25C) from Cobalt (II) Chloride
Hexahydrate/PR 254 Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PR 254
Mixture
[0249] To 4.0 g of PR 254 (IRGAPHOR RED BT-CF, from BASF Japan
Ltd.) is added 0.888 g of cobalt (II) chloride hexahydrate (from
Wako Pure Chemical Industries, Ltd.) and mixed in an agate mortar
to prepare a cobalt (II) chloride hexahydrate/PR 254 mixture
(25A).
(2) Infusibilization and Carbonization
[0250] The mixture (25A) (1.000 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (25A) is heated at a rate
of temperature rise of 1.degree. C./min from 30.degree. C. to
300.degree. C. and then at 10.degree. C./min from 300.degree. C. to
800.degree. C., maintained at 800.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.328 g
of a carbon material (25B).
(3) Grinding and Acid Cleaning
[0251] The carbon material (25B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (25C).
Example 26
Synthesis of Carbon Material (26C) from Cobalt (II) Chloride
Hexahydrate/PY 138 Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PY 138
Mixture
[0252] To 4.0 g of Pigment Yellow 138 (PY 138) (PALIOTOL YELLOW P09
60, from BASF Japan Ltd.) is added 0.457 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride hexahydrate/PY
138 mixture (26A).
(2) Infusibilization and Carbonization
[0253] The mixture (26A) (1.041 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (26A) is heated at a rate
of temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.559 g of a
carbon material (26B).
(3) Grinding and Acid Cleaning
[0254] The carbon material (26B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (26C).
##STR00025##
Molecular formula: C.sub.26H.sub.6Cl.sub.8N.sub.2O.sub.4 Molecular
weight: 693.961 Elemental analysis (calcd.): C, 45.00; H, 0.87; Cl,
40.87; N, 4.04; O, 9.22.
Example 27
Synthesis of Carbon Material (27C) from Cobalt (II) Chloride
Hexahydrate/PY 185 Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PY 185
Mixture
[0255] To 3.0 g of Pigment Yellow 185 (PY 185) (PALIOTOL YELLOW P11
55, from BASF Japan Ltd.) is added 0.701 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride hexahydrate/PY
185 mixture (27A).
(2) Infusibilization and Carbonization
[0256] The mixture (27A) (1.031 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (27A) is heated at a rate
of temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.362 g of a
carbon material (27B).
(3) Grinding and Acid Cleaning
[0257] The carbon material (27B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (27C).
##STR00026##
Molecular formula: C.sub.16H.sub.11N.sub.5O.sub.4 Molecular weight:
337.290 Elemental analysis (calcd.): C, 56.98; H, 3.29; N, 20.76;
O, 18.97.
Example 34
Synthesis of Carbon Material (34C) from Cobalt (II) Chloride
Hexahydrate/PY 109 Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PY 109
Mixture
[0258] To 4.00 g of Pigment Yellow 109 (PY 109) (IRGAZIN YELLOW
2GLTE, from BASF Japan Ltd.) is added 0.484 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/PY 109 mixture (34A).
(2) Infusibilization and Carbonization
[0259] The mixture (34A) (1.007 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (34A) is heated at a rate
of temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.506 g of a
carbon material (34B).
(3) Grinding and Acid Cleaning
[0260] The carbon material (34B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 110.degree. C. for 1
hour to obtain an acid cleaned carbon material (34C).
##STR00027##
Molecular formula: C.sub.23H.sub.8Cl.sub.8N.sub.4O.sub.2 Molecular
weight: 655.959 Elemental analysis (calcd.): C, 42.11; H, 1.23; Cl,
43.24; N, 8.54; O, 4.88.
Example 35
Synthesis of Carbon Material (35C) from Cobalt (II) Chloride
Hexahydrate/PY 110 Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PY 110
Mixture
[0261] To 4.00 g of Pigment Yellow 110 (PY 110) (IRGAZIN YELLOW
2RLT, from BASF Japan Ltd.) is added 0.494 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/PY 110 mixture (35A).
(2) Infusibilization and Carbonization
[0262] The mixture (35A) (1.031 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (35A) is heated at a rate
of temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.540 g of a
carbon material (35B).
(3) Grinding and Acid Cleaning
[0263] The carbon material (35B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 110.degree. C. for 1
hour to obtain an acid cleaned carbon material (35C).
##STR00028##
Molecular formula: C.sub.22H.sub.6Cl.sub.8N.sub.4O.sub.2 Molecular
weight: 641.933 Elemental analysis (calcd.): C, 41.16; H, 0.94; Cl,
44.18; N, 8.73; O, 4.98.
Example 36
Synthesis of Carbon Material (36C) from Cobalt (II) Chloride
Hexahydrate/PY 139 Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/PY 139
Mixture
[0264] To 4.00 g of Pigment Yellow 139 (PY 139) (Chromophtal Yellow
2RF, from BASF Japan Ltd.) is added 0.864 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride hexahydrate/PY
139 mixture (36A).
(2) Infusibilization and Carbonization
[0265] The mixture (36A) (1.020 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (36A) is heated at a rate
of temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours to obtain 0.331 g of a
carbon material (36B).
(3) Grinding and Acid Cleaning
[0266] The carbon material (36B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 110.degree. C. for 1
hour to obtain an acid cleaned carbon material (36C).
##STR00029##
Molecular formula: C.sub.16H.sub.9N.sub.5O.sub.6 Molecular weight:
367.273 Elemental analysis (calcd.): C, 52.32, H, 2.47; N, 19.07;
O, 26.14.
Example 28
Synthesis of Carbon Material (28C) from Cobalt (II) Chloride
Hexahydrate/1,2,4,5-Tetracyanobenzene (TCB) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/TCB Mixture
[0267] To 5.27 g of 1,2,4,5-tetracyanobenzene (TCB) (from Tokyo
Chemical Industry Co., Ltd.) is added 1.17 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/TCB mixture (28A).
(2) Infusibilization and Carbonization
[0268] The mixture (28A) (1.008 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (28A) is heated at a rate
of temperature rise of 5 C/min from 30.degree. C. to 700.degree.
C., maintained at 700.degree. C. for 1 hour, and cooled to room
temperature over a period of 30 minutes to obtain 0.071 g of a
carbon material (28B).
(3) Grinding and Acid Cleaning
[0269] The carbon material (28B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (28C).
1,2,4,5-Tetracyanobenzene
[0270] Molecular formula: C.sub.10H.sub.2N.sub.4 Molecular weight:
178.15 Elemental analysis (calcd.): C, 67.42; H, 1.13; N,
31.45.
Example 29
Synthesis of Carbon Material (29C) from Cobalt (II) Chloride
Hexahydrate/3,4,5,6-Tetrachlorophthalonitrile (TCPN) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/TCPN
Mixture
[0271] To 5.03 g of 3,4,5,6-tetrachlorophthalonitrile (TCPN) (from
Sigma Aldrich Corporation) is added 0.75 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride hexahydrate/TCPN
mixture (29A).
(2) Infusibilization and Carbonization
[0272] The mixture (29A) (1.004 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (29A) is heated at a rate
of temperature rise of 500.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.040 g
of a carbon material (29B).
(3) Grinding and Acid Cleaning
[0273] The carbon material (29B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (29C).
3,4,5,6-Tetrachlorophthalonitrile
[0274] Molecular formula: C.sub.5N.sub.2Cl.sub.4 Molecular weight:
265.91 Elemental analysis (calcd.): C, 36.13; H, 0.00; N, 10.53;
Cl, 53.33.
Example 30
Synthesis of Carbon Material (30C) from Cobalt (II) Chloride
Hexahydrate/7,7,8,8-Tetracyanoquinodimethane (TCNQ) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/TCNQ
Mixture
[0275] To 1.98 g of 7,7,8,8-tetracyanoquinodimethane (TCNQ) (from
Tokyo Chemical Industry Co., Ltd.) is added 0.384 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/TCNQ mixture (30A).
(2) Infusibilization and Carbonization
[0276] The mixture (30A) (1.004 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (30A) is heated at a rate
of temperature rise of 5.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.141 g
of a carbon material (30B).
(3) Grinding and Acid Cleaning
[0277] The carbon material (30B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (30C).
##STR00030##
7,7,8,8-Tetracyanoquinodimethane
[0278] Molecular formula: C.sub.12H.sub.4N.sub.4 Molecular weight:
204.187 Elemental analysis (calcd.): C, 70.59; H, 1.97; N,
27.44.
Example 31
Synthesis of Carbon Material (31C) from Cobalt (II) Chloride
Hexahydrate/2,3-Dichloro-5,6-Dicyano-1,4-Benzoquinone (DDQ)
Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/DDQ Mixture
[0279] To 4.00 g of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)
(from Wako Pure Chemical Industries, Ltd.) is added 0.699 g of
cobalt (II) chloride hexahydrate (from Wako Pure Chemical
Industries, Ltd.) and mixed in an agate mortar to prepare a cobalt
(II) chloride hexahydrate/DDQ mixture (31A).
(2) Infusibilization and Carbonization
[0280] The mixture (31A) (1.052 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (31A) is heated at a rate
of temperature rise of 5.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.042 g
of a carbon material (31B).
(3) Grinding and Acid Cleaning
[0281] The carbon material (31B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (31C).
##STR00031##
Molecular formula: C.sub.8Cl.sub.2N.sub.2O.sub.2 Molecular weight:
227.004 Elemental analysis (calcd.): C, 42.33; C, 31.24; N, 12.34;
O, 14.10.
Example 32
Synthesis of Carbon Material (32C) from Cobalt (II) Chloride
Hexahydrate/4,5-Dichlorophthalamide (DCPA) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/DCPA
Mixture
[0282] To 5.00 g of 4,5-dichlorophthalamide (DCPA) (from Tokyo
Chemical Industry Co., Ltd.) is added 0.85 g of cobalt (II)
chloride hexahydrate (from Wako Pure Chemical Industries, Ltd.) and
mixed in an agate mortar to prepare a cobalt (II) chloride
hexahydrate/DCPA mixture (32A).
(2) Infusibilization and Carbonization
[0283] The mixture (32A) (1.014 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (32A) is heated at a rate
of temperature rise of 5.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.041 g
of a carbon material (32B).
(3) Grinding and Acid Cleaning
[0284] The carbon material (32B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (32C).
4,5-Dichlorophthalamide
[0285] Molecular formula: C.sub.8H.sub.6N.sub.2O.sub.2Cl.sub.2
Molecular weight: 233.05 Elemental analysis (calcd.): C, 41.23; H,
2.59; N, 12.02; O, 13.73; Cl, 30.42.
Example 33
Synthesis of Carbon Material (33C) from Cobalt (II) Chloride
Hexahydrate/2,6-Dicyanopyridine (2,6-DCPy) Mixture
(1) Preparation of Cobalt (II) Chloride Hexahydrate/2,6-DCPy
Mixture
[0286] To 5.16 g of 2,6-dicyanopyridine (2,6-DCPy) (from Sigma
Aldrich Corporation) is added 1.58 g of cobalt (II) chloride
hexahydrate (from Wako Pure Chemical Industries, Ltd.) and mixed in
an agate mortar to prepare a cobalt (II) chloride
hexahydrate/2,6-DCPy mixture (33A).
(2) Infusibilization and Carbonization
[0287] The mixture (33A) (1.027 g) is weighed into a quartz boat.
The quartz boat is placed in the middle of a quartz tube (outer
diameter: 4.0 cm; inner diameter: 3.6 cm) inserted in a tubular
furnace. Nitrogen is made to flow at a rate of 300 ml/min for 30
minutes at room temperature. The mixture (33A) is heated at a rate
of temperature rise of 5.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 30 minutes to obtain 0.140 g
of a carbon material (33B).
(3) Grinding and Acid Cleaning
[0288] The carbon material (33B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (33C).
2,6-Dicyanopyridine
[0289] Molecular formula: C.sub.7H.sub.3N.sub.3 Molecular weight:
129.12 Elemental analysis (calcd.): C, 65.11; H, 2.34; N,
32.54.
Comparative Example 4
Synthesis of Carbon Material (C4C) from Cobalt Phthalocyanine
(Co-Pc)
(1) Infusibilization and Carbonization
[0290] Cobalt phthalocyanine (Co-Pc) (from Sigma Aldrich
Corporation) (1.005 g) is weighed into a quartz boat. The quartz
boat is placed in the middle of a quartz tube (outer diameter: 4.0
cm; inner diameter: 3.6 cm) inserted in a tubular furnace. Nitrogen
is made to flow at a rate of 300 ml/min for 30 minutes at room
temperature. The Fe-Pc is heated at a rate of temperature rise of
1.degree. C./min from 30.degree. C. to 300.degree. C. and then at
10.degree. C./min from 300.degree. C. to 700.degree. C., maintained
at 700.degree. C. for 1 hour, and cooled to room temperature over a
period of 3 hours to obtain 0.789 g of a carbon material (C4B).
(2) Grinding and Acid Cleaning
[0291] The carbon material (C4B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (C4C).
##STR00032##
Molecular formula: C.sub.32H.sub.16C0N.sub.8 Molecular weight:
571.456 Elemental analysis (calcd.): C, 67.26; H, 2.82; Co, 10.31;
N, 19.61.
Comparative Example 5
Synthesis of Carbon Material (C5C) from Co-PQ
(1) Synthesis of Polyquinolinol (PQ)
[0292] In a 100 ml recovery flask are put 10 g of 8-quinolinol, 10
g of formaldehyde, and 1 g of oxalic acid dihydrate and refluxed at
100.degree. C. overnight. To the mixture is added 5.5 ml of 1M HCl,
followed by refluxing under the same conditions overnight. The
resulting solid is collected by filtration by suction, washed three
times with distilled water, and dried in vacuo overnight to yield
PQ.
(2) Preparation of Cobalt Polyquinolinol Complex (Co-PQ)
[0293] In 100 ml of N,N-dimethylformamide is dissolved 3.3 g of PQ,
and a solution of 0.9 g of cobalt (II) chloride in 50 ml of
dimethylacetamide (DMAc) is added thereto. After allowing the mixed
solution to stand still overnight, the solution is concentrated
using an evaporator (90.degree. C.) and added dropwise to 3000 ml
of water. The precipitate thus formed is collected by filtration,
reprecipitated from DMAc, and collected by filtration to obtain a
cobalt polyquinolinol complex (Co-PQ). The composition of Co-PQ is
found to be Co(PQ).sub.3.
(3) Infusibilization and Carbonization
[0294] Co-PQ (1.001 g) is weighed into a quartz boat. The quartz
boat is placed in the middle of a quartz tube (outer diameter: 4.0
cm; inner diameter: 3.6 cm) inserted in a tubular furnace. Nitrogen
is made to flow at a rate of 300 ml/min for 30 minutes at room
temperature. The Co-PQ is heated at a rate of temperature rise of
1.degree. C./min from 30.degree. C. to 300.degree. C. and then at
10.degree. C./min from 300.degree. C. to 700.degree. C., maintained
at 700.degree. C. for 1 hour, and cooled to room temperature over a
period of 3 hours to obtain 0.522 g of a carbon material (C5B).
(4) Grinding and Acid Cleaning
[0295] The carbon material (C5B) is ground in an agate mortar. The
powder is washed with concentrated hydrochloride acid three times,
each followed by filtration, washed with water, and air dried. The
resulting carbon material is dried in vacuo at 60.degree. C.
overnight to obtain an acid cleaned carbon material (C5C).
##STR00033##
Molecular formula: (C.sub.10H.sub.7NO).sub.n Molecular weight (Mw):
14,000 Elemental analysis (calcd.): C, 76.42; H, 4.49; N, 8.91; O,
10.18.
Cobalt Polyquinolinol Complex (Co-PQ):
[0296] Molecular formula: (C.sub.30H.sub.21N.sub.3O.sub.3Co).sub.n
Formula weight: 530.44 Elemental analysis (calcd.): C, 67.9; H,
4.43; N, 7.92; O, 9.05; Co, 11.10.
Comparative Example 6
Synthesis of Carbon Material (C6C) from Cobalt (II) Chloride
Hexahydrate/Acetonitrile (MeCN) Mixture
Preparation of Cobalt (II) Chloride Hexahydrate/MeCN Mixture,
Infusibilization, and Carbonization
[0297] Acetonitrile (MeCN) (0.5 g) (from Wako Pure Chemical
Industries, Ltd.) and 0.50 g of cobalt (II) chloride hexahydrate
are weighed into a quartz boat. The quartz boat is placed in the
middle of a quartz tube (outer diameter: 4.0 cm; inner diameter:
3.6 cm) inserted in a tubular furnace. Nitrogen is made to flow at
a rate of 300 ml/min for 30 minutes at room temperature. The cobalt
(II) chloride hexahydrate/MeCN mixture is heated at a rate of
temperature rise of 10.degree. C./min from 30.degree. C. to
700.degree. C., maintained at 700.degree. C. for 1 hour, and cooled
to room temperature over a period of 3 hours. The resulting purple
residue (C6B) is washed with concentrated hydrochloride acid three
times, each followed by filtration, washed with water, and air
dried. Nothing remained on the filter paper, meaning a failure to
obtain a carbon material.
Evaluation of Physical Properties of Organic Material:
[0298] Heat resistance of the organic materials used in Examples 1
to 33 and Comparative Examples 3 to 5 is evaluated by determining a
percent mass loss (.DELTA.TG) at 400.degree. C. relative to the
mass at room temperature in TG-DTA analysis at a rate of
temperature rise of 10.degree. C./min from 30.degree. C. to
1000.degree. C. in a nitrogen atmosphere. TG-DTA analysis is
performed on EXSTAR 6000 series TG/DTA 6200 from SII Nanotechnology
Corporation. The results obtained are shown in Tables 1 to 3.
Making Carbon Alloy-Coated Electrode:
[0299] Each of the carbon alloy materials obtained in Examples 1 to
33 and Comparative Examples 1 to 6 weighing 10 mg is mixed with 110
mg of a Nafion solution (5% alcoholic aqueous solution) as a
binder, 2.4 ml of water and 1.6 ml of 1-propanol as solvents and
dispersed in an ultrasonic homogenizer (horn tip diameter: 7 mm)
(from Nippon Seiki Co., Ltd.) for 30 minutes. A 4 .mu.l aliquot of
the dispersion is applied to a rotating disk electrode and dried at
room temperature to make a carbon alloy-coated electrode. The
characteristics of the resulting carbon alloy-coated electrode are
evaluated as follows. The results obtained are shown in Tables 1 to
3.
Determination of ORR Activity:
[0300] Automatic polarization system HZ-3000 (from Hokuto Denko
Corp.) equipped with a disk electrode rotator HR-201 (from Hokuto
Denko) is used for linear sweep voltammetry (LSV) according to the
following procedures. The carbon alloy-coated electrode is set as a
working electrode. A platinum electrode and a saturated calomel
electrode (SCE) are used as a counter electrode and a reference
electrode, respectively.
Procedures:
[0301] (a) The carbon alloy-coated electrode is cleaned by cyclic
voltammetry in a 0.1M sulfuric acid aqueous solution at 20.degree.
C. through which argon had been bubbled for at least 30 minutes at
a sweep rate of 50 mV/s with a sweep potential ranging from 0.946
to -0.204 V (vs. SCE) for 10 cycles. (b) To obtain blank data, LSV
is carried out in a 0.1 M sulfuric acid aqueous solution at
20.degree. C. through which argon had been bubbled for at least 30
minutes at a sweep rate of 5 mV/s with a sweep potential ranging
from 0.746 to -0.204 V (vs. SCE) and at an electrode rotation speed
of 1500 rpm. (c) For ORR activity determination, LSV is performed
in a 0.5 M sulfuric acid aqueous solution through which oxygen had
been bubbled for at least 30 minutes at a sweep rate of 5 mV/s with
a sweep potential ranging from 0.746 to -0.204 V (vs. SCE) and at
an electrode rotation speed of 1500 rpm. (d) The blank data
obtained in (b) above is subtracted from the data of (c) to obtain
a true oxygen reduction current. The current density at the voltage
of 0.5 V (vs. NHE) is obtained from the resulting voltammogram
(voltage-current density curve, see FIG. 3), which is taken as an
ORR activity value.
BET Specific Surface Area:
[0302] The sample is dried at 200.degree. C. in vacuo for 3 hours
using a pretreatment instrument BELPREP-flow (from Bel Japan,
Inc.). The specific surface area measurement is performed using an
automatic specific surface area/pore distribution measurement
instrument BELSOPR-mini II (from Bel Japan, Inc.) under simplified
measuring conditions. Specific surface area analysis is carried out
by the BET method using the attached analysis program.
Raman Microscopy:
[0303] A dispersive Raman system T6400 (from HORIBA Jobin Yvon
Inc.) equipped with an Ar ion laser (514.5 nm excitation) and a
100.times. power objective (1 .mu.m resolution) is used to obtain a
Raman spectrum. The resulting Raman spectrum is subjected to wave
separation to be divided into D-band (C(sp3)) and G-band (C(sp2))
appearing at about 1320 cm.sup.-1 and about 1600 cm.sup.-1,
respectively. The full width at half maximum of the D-band
(.DELTA.D) is obtained, which is taken as a measure of
turbostraticity.
TABLE-US-00001 TABLE 1 Organic Material Composition .DELTA.TG at
400.degree. C. ORR Activity A BET Specific Turbostraticity A B C
(%) (.mu.A/cm.sup.2) Surface Area (m.sup.2/g) .DELTA.D (cm.sup.-1)
Example 1 PR 254 -1 -100 232 138 Comp. Example 1 PhOH -100 -- -- --
Comp. Example 2 MeCN -100 -- -- --
TABLE-US-00002 TABLE 2 Organic Material Composition .DELTA.TG at
400.degree. C. ORR Activity A BET Specific Turbostraticity A B C
(%) (.mu.A/cm.sup.2) Surface Area (m.sup.2/g) .DELTA.D (cm.sup.-1)
Example 2 PR 202 FeCl.sub.3.cndot.6H.sub.2O -25 -128 269 110
Example 3 PO 71 FeCl.sub.3.cndot.6H.sub.2O -25 -151 312 -- Example
4 PR 254 FeCl.sub.3 -10 -131 166 80 Example 5 PR 254
FeCl.sub.3.cndot.6H.sub.2O -27 -563 325 -- Example 6 PR 254-LP
FeCl.sub.3.cndot.6H.sub.2O -39 -730 321 -- Example 7 PR 254
FeCl.sub.3.cndot.6H.sub.2O -20 -250 374 83 Example 8 PR 254
FeCl.sub.2.cndot.4H.sub.2O -8 -302 394 103 Example 9 DCP
FeCl.sub.3.cndot.6H.sub.2O -56 -418 163 -- Comp. Example 3 Fe-Pc -6
-70 137 58
TABLE-US-00003 TABLE 3 .DELTA.TG at ORR BET Specific Turbo- Organic
Material Composition 400.degree. C. Activity A Surface straticity A
B C (%) (.mu.A/cm.sup.2) Area (m.sup.2/g) .DELTA.D (cm.sup.-1)
Example 10 DCP CoCl.sub.2.cndot.6H.sub.2O -70 -2094 361 84 Example
11 PR 122 CoCl.sub.2.cndot.6H.sub.2O -11 -105 91 101 Example 12
4-HPN CoCl.sub.2.cndot.6H.sub.2O -32 -119 89 -- Example 13 4,5-DHBN
CoCl.sub.2.cndot.6H.sub.2O -54 -244 244 -- Example 14 PN
CoCl.sub.2.cndot.6H.sub.2O -61 -1055 100 -- Example 15 PN
CoCl.sub.2.cndot.6H.sub.2O VB -45 -448 116 -- Example 16 4-HPN
CoCl.sub.2.cndot.6H.sub.2O VB -42 -795 132 -- Example 17 MN
CoCl.sub.2.cndot.6H.sub.2O -55 -774 199 -- Example 18 2-CBA
CoCl.sub.2.cndot.6H.sub.2O -67 -789 229 -- Example 19 3-CBA
CoCl.sub.2.cndot.6H.sub.2O -79 -766 108 -- Example 20 Cl--Ph--CN
CoCl.sub.2.cndot.6H.sub.2O -87 -500 29 -- Example 21 Cl--Ph--CN
CoCl.sub.2.cndot.6H.sub.2O KB -42 -478 662 -- Example 22 DCP
CoCl.sub.2.cndot.6H.sub.2O VB -48 -680 112 -- Example 23 PR 254-LP
CoCl.sub.2.cndot.6H.sub.2O -41 -967 387 -- Example 24 PR 254
Co(NO.sub.3).sub.2.cndot.6H.sub.2O -23 -1022 376 127 Example 25 PR
245 CoCl.sub.2.cndot.6H.sub.2O -10 -1067 319 145 Example 26 PY 138
CoCl.sub.2.cndot.6H.sub.2O -7 -583 180 -- Example 27 PY 185
CoCl.sub.2.cndot.6H.sub.2O -26 -1122 484 -- Example 34 PY 109
CoCl.sub.2.cndot.6H.sub.2O -6 -475 77 -- Example 35 PY 110
CoCl.sub.2.cndot.6H.sub.2O -6 -579 111 -- Example 36 PY 139
CoCl.sub.2.cndot.6H.sub.2O -22 -1410 234 -- Example 28 TCB
CoCl.sub.2.cndot.6H.sub.2O -83 -1693 63 -- Example 29 TCPN
CoCl.sub.2.cndot.6H.sub.2O -90 -1369 238 -- Example 30 TCNQ
CoCl.sub.2.cndot.6H.sub.2O -89 -1131 47 -- Example 31 DDQ
CoCl.sub.2.cndot.6H.sub.2O -92 -1359 86 -- Example 32 DCPA
CoCl.sub.2.cndot.6H.sub.2O -85 -2060 308 -- Example 33 2,6-DCPy
CoCl.sub.2.cndot.6H.sub.2O -84 -1339 165 -- Comp. Example 4 Co--Pc
-2 -35 134 -- Comp. Example 5 C--PQ -20 -32 134 40 Comp. Example 6
MeCN CoCl.sub.2.cndot.6H.sub.2O -- -- -- -- ##STR00034##
##STR00035## ##STR00036## ##STR00037## ##STR00038## ##STR00039##
##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044##
##STR00045##
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