U.S. patent application number 13/474860 was filed with the patent office on 2013-11-21 for process of dry milling particulate materials.
The applicant listed for this patent is Inhwan Do, Michael Knox, Scott Murray, Robert M. Privette. Invention is credited to Inhwan Do, Michael Knox, Scott Murray, Robert M. Privette.
Application Number | 20130309495 13/474860 |
Document ID | / |
Family ID | 49581534 |
Filed Date | 2013-11-21 |
United States Patent
Application |
20130309495 |
Kind Code |
A1 |
Do; Inhwan ; et al. |
November 21, 2013 |
PROCESS OF DRY MILLING PARTICULATE MATERIALS
Abstract
Graphene produced by media ball milling has very small particle
size, a relatively high surface area and unique aspect ratios. It
is uniquely suited to make nano-composites or coating by coating or
admixing other particles. Metals or metal oxides can be coated or
formed into composites with the high surface area, relatively low
aspect ratio graphene. If the added particles are larger than the
graphene, they are coated with graphene, and if they are about the
same approximate size, a nano-composite forms. The nanocomposites
are useful for producing electrodes, especially for battery and
supercapacitor applications.
Inventors: |
Do; Inhwan; (East Lansing,
MI) ; Knox; Michael; (East Lansing, MI) ;
Murray; Scott; (East Lansing, MI) ; Privette; Robert
M.; (East Lansing, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Do; Inhwan
Knox; Michael
Murray; Scott
Privette; Robert M. |
East Lansing
East Lansing
East Lansing
East Lansing |
MI
MI
MI
MI |
US
US
US
US |
|
|
Family ID: |
49581534 |
Appl. No.: |
13/474860 |
Filed: |
May 18, 2012 |
Current U.S.
Class: |
428/402 ;
106/286.1; 106/286.3; 106/286.8; 241/27; 252/182.11; 252/500;
252/503; 252/506; 252/509; 252/71; 502/100; 977/734; 977/773;
977/900 |
Current CPC
Class: |
C09D 1/00 20130101; Y02E
60/13 20130101; H01M 4/587 20130101; H01M 4/622 20130101; B82Y
40/00 20130101; H01M 4/04 20130101; H01M 4/48 20130101; B82Y 30/00
20130101; H01G 11/46 20130101; B02C 17/20 20130101; Y02E 60/10
20130101; H01G 11/36 20130101; H01M 4/386 20130101; C04B 35/6261
20130101; H01G 11/86 20130101; H01M 4/13 20130101; H01M 4/364
20130101; H01M 4/38 20130101; Y10T 428/2982 20150115; H01B 1/04
20130101 |
Class at
Publication: |
428/402 ;
502/100; 252/500; 252/182.11; 252/71; 252/503; 252/506; 252/509;
106/286.8; 106/286.3; 106/286.1; 241/27; 977/900; 977/773;
977/734 |
International
Class: |
C09K 3/00 20060101
C09K003/00; H01B 1/00 20060101 H01B001/00; C09K 5/00 20060101
C09K005/00; H01B 1/04 20060101 H01B001/04; B02C 17/00 20060101
B02C017/00; B02C 17/20 20060101 B02C017/20; B32B 5/16 20060101
B32B005/16; B01J 35/02 20060101 B01J035/02; C09D 1/00 20060101
C09D001/00 |
Claims
1. A process of dry milling particulate materials, wherein at least
one of the particulate materials is a layered material, in the
presence of a non-layered material, to obtain a composition wherein
the layered material is exfoliated and wherein the non-layered
material is composited with the exfoliated material, the exfoliated
material having a particle size of 10 microns by 5 nm thick, or
less, and wherein the dry milling is controlled by controlling the
surface energy of the milling media in addition to controlling the
hardness of the milling media.
2. The process as claimed in claim 1 wherein the non-layered
material is selected from the group consisting essentially of: i. a
particulate metal and, ii. a particulate metal oxide.
3. The process as claimed in claim 1 wherein the layered material
is graphite.
4. The process as claimed in claim 1 wherein the milling media has
a surface energy essentially equivalent to the surface energy of
the layered material.
5. The process as claimed in claim 1 wherein the milling media has
a hardness on the Brinell Scale in the range of 3 to 100.
6. The process as claimed in claim 1 wherein the exfoliated
material has an aspect ratio of greater than about 25.
7. The process as claimed in claim 1 wherein the exfoliated
material has an aspect ratio of from 5 to 200.
8. The process as claimed in claim 1 wherein the exfoliated
material has a size in the range of from 50 nm to 10 microns.
9. The process as claimed in claim 1 wherein the exfoliated
material has a thickness of from 1 nm to 5 nm.
10. The process as claimed in claim 1 wherein the milling media is
plastic material.
11. The process as claimed in claim 10 wherein the plastic is
selected from the group consisting essentially of: i.
polymethylmethacrylate, ii. polycarbonate, iii. polystyrene, iv.
polypropylene, v. polyethylene, vi. polytetrafluoroethylene, vii.
polyethyleneimide, viii. polyvinylchloride, ix. polyamine-imide,
and, x. alloys of any of i. to ix.
12. The process as claimed in claim 2 wherein the particulate
metals are selected from the group consisting essentially of: i.
silicon, ii. tin, iii. iron, iv. magnesium, v. manganese, vi.
aluminum, vii. lead, viii. gold, ix. silver, x. titanium, xi.
platinum, xii. palladium, xiii. ruthenium, xiv. copper, xv. nickel,
xvi. rhodium, and, xvii. alloys of any of i. to xvi.
13. The process as claimed in claim 2 wherein the particulate metal
oxides are selected from the group consisting essentially of oxides
of: i. silicon, ii. tin, iii. iron, iv. magnesium, v. manganese,
vi. aluminum, vii. lead, viii. gold, ix. silver, x. titanium, xi.
platinum, xii. palladium, xiii. ruthenium, xiv. copper, xv. nickel,
xvi. rhodium, and, xvii. alloys of any of i. to xvi.
14. The process as claimed in claim 1 wherein the particulate
non-layered material has a size less than 100 microns.
15. The process as claimed in claim 1 wherein the particulate are
metal carbides.
16. The process as claimed in claim 1 wherein the particulate
materials are metal nitrides.
17. A product when produced by the process of claim 1.
18. An electrode produced from the product as claimed in claim
17.
19. A catalyst produced from the product as claimed in claim
17.
20. A coating produced from the product as claimed in claim 17.
21. An electronic component manufactured from the product as
claimed in claim 17.
22. A thermally conductive component manufactured from the product
as claimed in claim 17.
23. A process of dry milling particulate materials, wherein at
least one of the particulate materials is a layered material, in
the presence of a particulate material selected from the group
consisting of i. ceramic, ii. glass, and iii. quartz, to obtain a
composition wherein the layered material is exfoliated and wherein
the particulate material is coated with the exfoliated material,
the exfoliated material having a particle size of 500 nanometers or
less, and wherein the dry milling is controlled by controlling the
surface energy of the milling media in addition to controlling the
hardness of the milling media.
24. A process of dry milling particulate materials, wherein at
least one of the particulate materials is a layered material, in
the presence of a particulate material selected from the group
consisting of i. ceramic, ii. glass, and iii. quartz, to obtain a
composition wherein the layered material is exfoliated and wherein
the particulate material is coated with the exfoliated material,
the exfoliated material having a particle size of 10 microns or
more, and the wherein the dry milling is controlled by controlling
the surface energy of the milling media in addition to controlling
the hardness of the milling media.
25. A composition of matter comprising particles composited with
graphene wherein the particles are selected from the group
consisting essentially of metal particles, and metal oxide
particles, wherein the metal and metal oxide particles have a size
of 100 microns or smaller.
26. A composition of matter as claimed in claim 25 wherein the
metal and metal oxide particles have a size of 100 microns or
less.
27. A composition of matter as claimed in claim 25 wherein the
metal and metal oxide particles have a size of 10 microns or
less.
28. A composition of matter as claimed in claim 25 wherein the
metal and metal oxide particles have a size of 1 micron or
less.
29. A composition of matter as claimed in claim 25 wherein the
graphene is less than 5 nm thick.
30. A composition of matter as claimed in claim 25 wherein the
graphene is a monolayer thick.
31. A composition of matter as claimed in claim 25 wherein the
oxygen content of the graphene is ten atomic weight percent or
less.
32. A composition of matter as claimed in claim 25 wherein the
metal is selected from the group consisting essentially of iron,
magnesium, cobalt, molybdenum, and lead.
33. A composition of matter as claimed in claim 25 wherein the
metal oxide is selected from the group of oxides consisting
essentially of iron oxide, magnesium oxide, cobalt oxide,
molybdenum oxide, and lead oxide.
34. A composition of matter as claimed in claim 25 wherein the size
of the graphene particle is less than 5 microns.
35. A composition of matter as claimed in claim 25 wherein the
surface area of the graphene is greater than about 300 m.sup.2/g
BET.
36. A composition of matter as claimed in claim 25 wherein the
metal particles are larger than the graphene composited with
them.
37. A composition of matter as claimed in claim 25 wherein the
metal particle are essentially the same size as the graphene they
are combined with.
38. A composition of matter as claimed in claim 25 that is a
nanocomposite.
39. An electrode manufactured from the composition of claim 25.
40. A battery comprising at least one electrode as claimed in claim
39.
41. A capacitor comprising an electrode as claimed in claim 39.
Description
BACKGROUND OF THE INVENTION
[0001] This invention deals with graphene platelet nano composites
with metal or metal oxide, and graphene platelet nano coated with
metal or metal oxide. The coated and composited particles are
useful as electrodes and for electrical applications.
[0002] Graphite is formed by many layers of carbon in highly
structured platelets. These platelets, when separated from the
graphite superstructure, are collectively called graphene. Graphene
has interesting chemical, physical, and electrical properties.
These properties make graphene a highly valued product. The quality
of the graphene, as defined by particle diameter, particle width,
and surface area, determine its industrial utility. It is
advantageous to coat or composite graphene with metal particles for
electrical applications.
[0003] Xg Sciences, Inc. headquartered in Lansing, Mich. produces a
"C" grade graphene by a high energy, plastic media, dry, mechanical
milling process. Grade size characteristics make it uniquely suited
to coating or mixing with nanoparticles to form useful materials
for electrodes.
[0004] The applicant is aware of U.S. Patent publication
2011/0111303 A1 that published on May 12, 2011 as showing a wet
process for treating graphene with silicon.
[0005] Also, the patentees are aware of EP2275385 in the name of
Peukert, et al in which a wet process is set forth for grinding
particulate materials, wherein the grinding media is yttrium
stabilized zirconia.
SUMMARY OF THE INVENTION
[0006] Graphene produced by media ball milling has very small
particle size with a relatively high surface area. It is uniquely
suited to make nano-composites or coatings by coating or admixing
other particles. Metals or metal oxides can be coated or formed
into composites with the high surface area, relatively low aspect
ratio graphene. It is believed by the inventors herein that the
materials of this invention have unique aspect ratios. Ground
graphite admixed with silicon has an aspect ratio fairly close to
1, graphene from a GO process, epitaxially grown graphene, or
graphene from an intercalated--heating process has a very high
aspect ratio. The moderate aspect ratio graphene of this invention
better coats 1 to 4 micron particles and better mixes with even
small nano-particles.
[0007] Based on Raman spectroscopy with the aspect ratio, particle
size, and/or surface area, provides graphene in this invention that
is unique.
[0008] Based on the following table calculated from Raman
Spectroscopy and measuring peak height, generated the following
table.
TABLE-US-00001 m.sup.2/g G D G/D Gpeak 250 50 5 10 1580 400 19 6
3.2 500 21 7 3 600 16 6 2.7 1585
[0009] Native graphite has a very high G/D ratio. Graphite ground
to amorphous powder has the G/D ratio. the material of the instant
invention starts high and tends toward 2 the more the material is
processed. Amorphous graphite also has a G peak red shift to 2000
cm.sup.-1. The material of the instant invention may have a small
red shift, but from the quality of the data it is hard to
determine. The very high surface area and aspect ratio confirms it
is largely graphene nano-platelets.
[0010] Mechanically exfoliated graphene is distinct from ground
graphite, in that, it maintains the strong crystalline sp2
structure. As graphite is ground to amorphous, the ratio of G to D
Raman lines tends to 2 and the G line red shifts from 1560
cm.sup.-1 to 2000 cm.sup.-1. The G peak is referred to as the
graphene peak. The D peak referred to as the Disorder peak. The
more graphite is ground, the more the G peak is reduced and the D
peak is increased.
[0011] If the added particles are larger than the graphene, they
are coated with graphene, and if they are about the same
approximate size, a nano-composite forms. The nanocomposites are
useful for producing electrodes, especially for battery and
capacitor applications.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a graph of battery performance of a Si/graphene
(200-250 m.sup.2/g, 100 minutes processing time).
THE INVENTION
[0013] Thus, in one embodiment, there is a process of dry milling
particulate materials, wherein at least one of the particulate
materials is a layered material, in the presence of a non-layered
material, to obtain a composition wherein the layered material is
exfoliated and wherein the non-layered material is composited with
the exfoliated material.
[0014] The exfoliated material has a particle size of 10 microns by
5 nm thick, or less. In addition, the dry milling is controlled by
controlling the surface energy of the milling media in addition to
controlling the hardness of the milling media.
[0015] In a second embodiment, that is a process of dry milling
particulate materials, wherein at least one of the particulate
materials is a layered material, in the presence of a particulate
material selected from the group consisting of i. ceramic, ii.
glass, and iii. quartz, to obtain a composition wherein the layered
material is exfoliated and wherein the particulate material is
coated with the exfoliated material.
[0016] The exfoliated material has a particle size of 500
nanometers or less. In addition, the dry milling is controlled by
controlling the surface energy of the milling media in addition to
controlling the hardness of the milling media.
[0017] In, a fourth embodiment, there is a composited product
obtained by the first embodiment and a coated product obtained by
the second embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The graphene produced by the methods of this invention has a
relatively narrow aspect ratio, greater than graphite. For this
invention aspect ratios above 5 and below 200 are preferred and
more preferred are aspect ratios above 10 and below 25.
[0019] The small, that is, 1 to 5 nanometers thick, and 50 to 100
nanometers diameter, high surface area (above 500 BET), medium
aspect ratio graphene, is a unique size for coating with small
metal or metal oxide particles.
[0020] The metals useful in this invention are the metalloid
silicon, and the metals tin, iron, magnesium, manganese, aluminum,
lead, gold, silver, titanium, platinum, palladium, ruthenium,
copper, nickel, rhodium, and alloys of any of the above.
[0021] The plastic milling media useful in this invention has a
hardness on the Brinell Scale in the range of 3 to 100. The plastic
milling media is selected from the group consisting essentially of
polyacetals, polyacrylates, such as, for example,
methylmethacrylate, polycarbonate, polystyrene, poly-propylene,
polyethylene, polytetrafluoroethylene, polyethylene-imide,
polyvinylchloride, polyamine-imide, phenolics and
formaldehyde-based thermosetting resins, and alloys of any of the
plastics named.
[0022] The particulate metal oxides useful in this invention are
metal oxides selected from silicon, tin, iron, magnesium,
manganese, aluminum, lead, gold, silver, titanium, platinum,
palladium, ruthenium, copper, nickel, rhodium, tungsten, cobalt,
molybdenum, and alloys of any the above named metal oxides, wherein
the metal and metal oxide particles have a size of 100 microns or
less. Preferred are particle sizes of 10 microns or less, and most
preferred are particle sizes of 5 microns or less.
[0023] Metal carbides, metal nitrides are useful in this invention,
as well as non-layered materials.
[0024] Graphene useful in this invention is preferred to have a
thickness of 5 nm or less.
EXAMPLES
Example 1
[0025] Two grams of natural graphite and 1 g of micron sized Si (1
to 4 um) were loaded into a 65 ml stainless steel grinding
container and milled in the presence of 24 g of
polymethyl-methacrylate balls. The polymethylmethacrylate balls
consisted of two different sizes, namely, 1/4 inches and 3/8 inches
in diameter. The high energy milling machine was operated at
<1500 rpm and its clamp speed was 1060 cycle/min. The
polymethylmeth-acrylate balls can be replaced with polycarbonate,
polystyrene, polypropylene, polyethylene, polytetrafluoroethylene,
polyethyleneimide, polyvinylchloride and polyamide-imide to control
milling efficiency, graphene size, porosity distribution and
surface area at a fixed milling time, contact quality between Si
and graphene surface. The surface area of the Si/graphene composite
produced can be varied from 100 m.sup.2/g to 700 m.sup.2/g
depending on milling time (60 to 500 min.) and Si/graphene
composition and type of ball materials.
[0026] The result for the battery performance of a Si/graphene (200
to 250 m.sup.2/g, 100 min. processing) sample as an anode for a
lithium ion battery is plotted infra. The Si/graphene shows high
capacity (>800 mAh/g, electrode loading) over 35 cycles at 100
mA/g, which supports the low cost, simple, time-saving,
environmentally benign, flexible way to produce high performance
graphene-based composite materials for energy applications. Some
fluctuation of the capacity is due to the variation of
temperature.
Example 2
[0027] Two grams of natural graphite and 1 g of nano sized metal
oxides (Fe.sub.2O.sub.3, NiO, CoO.sub.3, MnO.sub.3) were loaded in
a 65 ml stainless steel grinding container and milled in the
presence of 24 g of polymethylmethyacrylate balls. The products can
be used as anode materials for lithium batteries and electrodes for
supercapacitors.
* * * * *