U.S. patent application number 14/437570 was filed with the patent office on 2015-10-22 for heat conversion member and heat conversion laminate.
The applicant listed for this patent is Japan Fine Ceramics Center, KABUSHIKI KAISHA TOYOTA JIDOSHOKKI. Invention is credited to Kazuto NORITAKE, Yoshiki OKUHARA, Toru SASATANI, Seiichi SUDA, Norihito TAKEUCHI, Takuhito TSUTSUI.
Application Number | 20150300695 14/437570 |
Document ID | / |
Family ID | 50544521 |
Filed Date | 2015-10-22 |
United States Patent
Application |
20150300695 |
Kind Code |
A1 |
TAKEUCHI; Norihito ; et
al. |
October 22, 2015 |
HEAT CONVERSION MEMBER AND HEAT CONVERSION LAMINATE
Abstract
The present invention addresses the problem of providing a heat
conversion member capable of efficiently converting light to heat.
This heat conversion member is characterized in that it includes a
composite material of at least one type of semiconductor and at
least one type of metal material.
Inventors: |
TAKEUCHI; Norihito;
(Kariya-shi, JP) ; NORITAKE; Kazuto; (Kariya-shi,
JP) ; SASATANI; Toru; (Kariya-shi, JP) ;
TSUTSUI; Takuhito; (Kariya-shi, JP) ; OKUHARA;
Yoshiki; (Nagoya-shi, JP) ; SUDA; Seiichi;
(Nagoya-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
Japan Fine Ceramics Center |
Kariya-shi, Aichi
Nagoya-shi, Aichi |
|
JP
JP |
|
|
Family ID: |
50544521 |
Appl. No.: |
14/437570 |
Filed: |
October 11, 2013 |
PCT Filed: |
October 11, 2013 |
PCT NO: |
PCT/JP2013/077828 |
371 Date: |
April 22, 2015 |
Current U.S.
Class: |
126/676 |
Current CPC
Class: |
F24S 70/225 20180501;
Y02E 10/40 20130101; F24S 70/12 20180501; H01L 31/0256 20130101;
F24S 70/16 20180501 |
International
Class: |
F24J 2/48 20060101
F24J002/48 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 26, 2012 |
JP |
2012-237295 |
Claims
1-8. (canceled)
9. A light-to-heat conversion member comprising a composite
material of one or more kinds of semiconductor and one or more
kinds of metal material.
10. The light-to-heat conversion member according to claim 9,
wherein the metal material is in the form of particles.
11. The light-to-heat conversion member according to claim 9,
wherein the semiconductor comprises FeSiX (X=0.5-4).
12. The light-to-heat conversion member according to claim 11,
wherein X in FeSiX is 2.
13. The light-to-heat conversion member according to claim 9, which
has a film shape.
14. The light-to-heat conversion member according to claim 13,
wherein the film shape has a thickness of 1 nm to 10 .mu.m.
15. A light-to-heat conversion laminate having laminated at least
one or more layers including the light-to-heat conversion member
according to claim 13, and a metal layer.
16. A light-to-heat conversion laminate having laminated at least a
metal layer, one or more layers including the light-to-heat
conversion member according to claim 13, and a transparent
dielectric layer, in that order.
Description
TECHNICAL FIELD
[0001] The present invention relates to a heat conversion member
and to a heat conversion laminate.
BACKGROUND ART
[0002] Photovoltaic power generation systems are known that convert
sunlight to heat and utilize the heat for electric power
generation. In the known systems, sunlight is collected with a
collector and the collected sunlight is used to heat a heating
medium (such as oil, dissolved salts or molten sodium) in a
container or flow channel. Provision of covering materials,
thin-films and the like on the surfaces of containers or flow
channels is also being studied as a way of accelerating heating of
the heating medium by the collected sunlight.
[0003] In NPL 1, for example, a covering material is provided on
the surface of a container or flow channel, and the covering
material promotes absorption of collected sunlight while minimizing
heat release by heat radiation from the container or flow channel
to the exterior. As another example, PTL 1 proposes a method for
producing a solar heat collector comprising a first glass tube
having a vacuum interior and allowing sunlight to impinge from the
exterior, and a second glass tube or metal tube provided on the
inner side of the first glass tube and having a selective absorbing
film on the surface, the selective absorbing film being composed of
a metal film that contacts with the second glass tube or metal tube
and a dielectric thin-film adhering onto the metal film, wherein
the metal film is formed by an electroless plating method selected
from among nickel, cobalt, silver and copper plating, and the
dielectric thin-film is formed by coating a film by a method of
coating a solution of one kind or a mixture selected from among
titanium dioxide, tantalum pentoxide and niobium pentoxide,
followed by heat treatment of the film at 500.degree. C. or higher
in an oxidizing atmosphere. Also, PTL 2 proposes a coating
composition for the heat-collecting surface of a solar heat
collector, comprising a pigment with a high solar absorption rate
that is highly permeable to infrared rays, polymethylpentene, and a
solvent that dissolves polymethylpentene, while PTL 3 proposes a
solar heat collecting apparatus utilizing sunlight energy, the
solar heat collecting apparatus comprising a wavelength converter
that absorbs at least a portion of sunlight and converts it to
light of a different wavelength, and a heat accumulator that
absorbs light emitted from the wavelength converter and generates
heat. In addition, PTL 4 proposes a sunlight selective absorption
coating having a sunlight absorbing property and low emissivity,
the sunlight selective absorption coating comprising a support (1)
of a metal, dielectric material or ceramic material, at least one
mid-to-far-infrared ray highly-reflecting metal layer (2)
accumulated on the support (1), a multilayer absorbing structure
(3) composed of an alternating dielectric layer (5) and metal layer
(6), accumulated on the metal reflective layer (2), and at least
one anti-reflection dielectric layer (4), accumulated on the
multilayer absorbing structure (3), the dielectric layers (5) of
the multilayer absorbing structure (3) being either of the same or
different thicknesses and/or compositions, the metal layers (6) of
the multilayer absorbing structure (3) being either of the same or
different thicknesses and/or compositions, the respective
thicknesses of the metal layers (6) and dielectric layers (5) of
the multilayer absorbing structure (3) being less than 10 nm and
preferably less than 1 nm, the total thickness of the multilayer
absorbing structure (3) being 5-1000 nm, wherein it is specified
that the layer of the dielectric material of the sunlight selective
absorption coating is accumulated by reactive sputtering including
an inert gas and a reactive gas in a chamber or a part of a chamber
in which the dielectric layer is to be accumulated, and the metal
layer of the sunlight selective absorption coating is accumulated
by DC sputtering, introducing only an inert gas into a chamber or
part of a chamber in which the metal sheet is to be
accumulated.
CITATION LIST
Patent Literature
[0004] [PTL 1] Japanese Unexamined Patent Publication No. 59-056661
[0005] [PTL 2] Japanese Unexamined Patent Publication No. 58-001760
[0006] [PTL 3] Japanese Unexamined Patent Publication No.
2010-002077 [0007] [PTL 4] Japanese Patent Public Inspection No.
2012-506021
Non Patent Literature
[0007] [0008] [NPL 1] July 2002, NREL/TP-520-31267, "Review of
Mid-to High-Temperature Solar Selective Absorber Materials", C. E.
Kennedy.
SUMMARY OF INVENTION
Technical Problem
[0009] At the current time, it is desirable to achieve more
accelerated heating of heating media by collected sunlight and
achieve more efficient light-to-heat conversion.
[0010] It is an object of the present invention to provide a heat
conversion member that can efficiently convert light to heat. It is
another object of the present invention to provide a heat
conversion laminate comprising a heat conversion member that can
efficiently convert light to heat.
Solution to Problem
[0011] The means for achieving these objects is described by the
following (1) to (8).
[0012] (1) A heat conversion member comprising a composite material
of one or more kinds of semiconductor and one or more kinds of
metal material.
[0013] (2) The heat conversion member according to (1), wherein the
metal material is in the form of particles.
[0014] (3) The heat conversion member according to (1) or (2),
wherein the semiconductor comprises FeSi.sub.X (X=0.5-4).
[0015] (4) The heat conversion member according to (3), wherein X
in FeSi.sub.X is 2.
[0016] (5) The heat conversion member according to any one of (1)
to (4), which is film-shaped.
[0017] (6) The heat conversion member according to (5), wherein the
film shape has a thickness of 1 nm to 10 .mu.m.
[0018] (7) A heat conversion laminate having laminated at least one
or more layers including at least the heat conversion member
according to (5) or (6), and a metal layer.
[0019] (8) A heat conversion laminate having laminated at least a
metal layer, one or more layers including at least the heat
conversion member according to (5) or (6), and a transparent
dielectric layer, in that order.
Advantageous Effects of Invention
[0020] According to the present invention, there is provided a heat
conversion member that can efficiently convert light to heat.
According to the present invention, there is further provided a
heat conversion laminate comprising a heat conversion member that
can efficiently convert light to heat.
BRIEF DESCRIPTION OF DRAWINGS
[0021] FIG. 1 is a cross-sectional schematic drawing showing a heat
conversion laminate 1 as one embodiment of a heat conversion
laminate according to the present invention.
[0022] FIG. 2 is a graph showing the results for the absorption
properties of a Ag--FeSi.sub.2 "metasemi" monolayer film.
[0023] FIG. 3 is a graph showing the results for the absorption
properties of a Mo--FeSi.sub.2 "metasemi" monolayer film.
[0024] FIG. 4 is a graph showing the results for the absorption
properties of a Cu--FeSi.sub.2 "metasemi" monolayer film.
DESCRIPTION OF EMBODIMENTS
(1) Heat Conversion Member
[0025] The heat conversion member of the present invention is a
heat conversion member comprising a composite material of one or
more kinds of semiconductor and one or more kinds of metal
material. The heat conversion member of the present invention
allows the absorption property for sunlight to be varied by
adjusting the content (addition rate) of the one or more kinds of
metal material, thereby allowing efficient conversion of light to
heat with improved optical selectivity. Here, "optical selectivity"
refers to dramatic change in the optical characteristics, such as
reflectance at certain wavelengths or certain wavelength
ranges.
[0026] The one or more kinds of semiconductor in the composite
material in the heat conversion member of the present invention
(also referred to as "composite material") may be of a single kind
of semiconductor, or a mixture of two or more different kinds of
semiconductor.
[0027] The semiconductor of a composite material in the heat
conversion member of the present invention is not particularly
restricted, and may be FeSi.sub.X (X=0.5-4), for example.
[0028] The one or more kinds of metal material in the composite
material in the heat conversion member of the present invention may
also be a single kind of metal material or a mixture of two or more
different kinds of metal material.
[0029] The metal material in the composite material in the heat
conversion member of the present invention is not particularly
restricted and may be an Ag material, Mo material or Cu material,
for example.
[0030] The one or more kinds of metal material in the composite
material in the heat conversion member of the present invention may
be in any desired form, but is preferably in the form of particles.
If the one or more kinds of metal material is in particle form, it
may be metallic particles or metal fine particles. The particle
diameter of particles of the metal material is preferably 1-100
nm.
[0031] The one or more kinds of semiconductor in the composite
material in the heat conversion member of the present invention
preferably contains FeSi.sub.X (X=0.5-4) and more preferably
contains FeSi.sub.2.
[0032] The heat conversion member of the present invention may be
in any desired form, such as in the form of a film shape, tube
shape, sheet shape or the like, however a film shape is preferred.
The thickness of a film of the heat conversion member of the
present invention may be any desired thickness so long as the
effect of the present invention is exhibited, however preferably a
film of the heat conversion member of the present invention has a
thickness of 1 nm to 10 .mu.m, and more preferably it has a
thickness of 5 nm to 100 nm.
[0033] The content of the one or more kinds of metal material in
the heat conversion member of the present invention may be as
desired, such as 1-50 vol %, for example.
[0034] The heat conversion member of the present invention may yet
also contain any desired material other than a composite material
of the one or more kinds of semiconductor and one or more kinds of
metal materials. For example, a transparent dielectric material
such as SiO.sub.2 may be mixed in the form of particulates or fine
particulates.
[0035] The heat conversion member of the present invention can be
obtained by any desired publicly known production method. For
example, the heat conversion member of the present invention can be
produced by physical vapor phase deposition (PVD), sputtering or
the like.
(2) Heat Conversion Laminate
[0036] As one feature, the heat conversion laminate of the present
invention has laminated one or more layers comprising a film-like
heat conversion member of the present invention, and a metal layer,
and it may have a metal layer and one or more layers comprising a
film-like heat conversion member of the present invention laminated
in that order, or the lamination may be in the reverse order.
[0037] As another feature, the heat conversion laminate of the
present invention also have at least a metal layer, one or more
layers comprising a film-like heat conversion member of the present
invention and a transparent dielectric layer, laminated in that
order.
[0038] The one or more layers containing a film-like heat
conversion member of the present invention in the heat conversion
laminate of the present invention may be constructed as a
photoabsorbing layer, and this allows the absorption property for
sunlight to be varied by adjusting the content of the one or more
kinds of metal material, thereby allowing efficient conversion of
light to heat with improved optical selectivity. The thickness of
the one or more layers comprising a film-like heat conversion
member in the heat conversion laminate of the present invention may
be any desired thickness so long as the effect of the present
invention is exhibited, and it is preferably a thickness of 5 nm to
100 nm. The layer comprising the film-like heat conversion member
in the heat conversion laminate of the present invention may be a
single layer or multiple layers. The one or more layers comprising
a film-like heat conversion member in the heat conversion laminate
of the present invention may also include any materials other than
the film-like heat conversion member.
[0039] The metal layer in the heat conversion laminate of the
present invention may be constructed as an infrared anti-reflection
layer. The metal layer in the heat conversion laminate of the
present invention is not particularly restricted, and for example,
it may be a molybdenum (Mo) layer, tungsten (W) layer, silver (Ag)
layer, gold (Au) layer, copper (Cu) layer or the like, and is
preferably a molybdenum (Mo) layer. The thickness of the metal
layer in the heat conversion laminate of the present invention may
have any desired thickness so long as the effect of the present
invention is exhibited, and it is preferably a thickness of 100 nm
or greater.
[0040] The transparent dielectric layer in the heat conversion
laminate of the present invention may also be constructed as an
anti-reflection layer. The transparent dielectric layer in the heat
conversion laminate of the present invention is not particularly
restricted, and examples include a SiO.sub.2 layer, Al.sub.2O.sub.3
layer, AlN layer or the like, with a SiO.sub.2 layer being
preferred. The thickness of the transparent dielectric layer in the
heat conversion laminate of the present invention may be any
desired thickness so long as the effect of the present invention is
exhibited, and it is preferably a thickness of 10 nm to 500 nm.
[0041] The heat conversion laminate of the present invention may
also include an absorbing layer other than a heat conversion member
of the present invention, as a photoabsorbing layer.
[0042] The heat conversion laminate of the present invention can be
obtained by any desired publicly known production method. For
example, the heat conversion laminate of the present invention can
be produced by physical vapor phase deposition (PVD), sputtering or
the like.
[0043] The heat conversion laminate of the present invention will
now be explained in greater detail with reference to FIG. 1.
Incidentally, the heat conversion laminate of the present invention
is not limited to the embodiment of the present invention shown in
FIG. 1, such as is within the scope of the object and gist of the
present invention.
[0044] FIG. 1 is a drawing showing a heat conversion laminate 1 as
one embodiment of a heat conversion laminate according to an
embodiment of the present invention. The heat conversion laminate 1
according to an embodiment of the present invention is formed from
a transparent dielectric layer 11, a layer comprising a heat
conversion member (photoabsorbing layer) 12, and a metal layer 13.
Also, the layer comprising a heat conversion member (photoabsorbing
layer) 12 comprises metal fine particles 121 and a semiconductor
122. As shown in FIG. 1, the metal fine particles 121 are dispersed
within the semiconductor 122.
EXAMPLES
[0045] Examples will now be provided for a more concrete
explanation of the present invention. The present invention is not
limited to these examples, however, provided that the object and
gist of the present invention are maintained.
<Evaluation of Absorption Properties of Heat Conversion
Member>
[0046] The absorption properties of heat conversion members were
evaluated using Examples 1 to 3 and Comparative Example 1.
Example 1
[0047] The absorption properties of a heat conversion member of the
present invention were evaluated using an Ag--FeSi.sub.2 "metasemi"
monolayer film. The term "metasemi" means
"metal+semiconductor".
[Method of Forming Ag--FeSi.sub.2 Metasemi Monolayer Film]
[0048] On a quartz substrate at room temperature, FeSi.sub.2 and Ag
(silver) were simultaneously sputtered to form a film. Following
film formation, annealing was performed for 1 hour in a vacuum
furnace at a temperature of no higher than 800.degree. C. Two
Ag--FeSi.sub.2 metasemi samples with different Ag (silver) addition
rates (4.0 vol %, 8.6 vol %) were prepared.
[0049] The optical constants (refractive index n, extinction
coefficient k) of the Ag--FeSi.sub.2 metasemi were calculated for
the obtained sample from the measurement data with a spectroscopic
ellipsometer and the reflectance property and transmittance
property measured with a spectrophotometer.
[0050] The calculated multilayer film approximation based on the
optical constants (n, k) for Ag--FeSi.sub.2 metasemi was used to
calculate the absorption rate of the Ag--FeSi.sub.2 metasemi
monolayer film (corresponding to a film thickness of 30 nm). FIG. 2
shows the results for the absorption properties of a Ag--FeSi.sub.2
metasemi monolayer film.
Example 2
[0051] The absorption properties of a heat conversion member of the
present invention were evaluated using a Mo--FeSi.sub.2 metasemi
monolayer film.
[Method of Forming Mo--FeSi.sub.2 Metasemi Monolayer Film]
[0052] On a quartz substrate heated to a temperature no higher than
700.degree. C., FeSi.sub.2 and Mo (molybdenum) were simultaneously
sputtered to form a film. Two Mo--FeSi.sub.2 metasemi samples with
different Mo (molybdenum) addition rates (4.2 vol %, 9.4 vol %)
were prepared.
[0053] The optical constants (refractive index n, extinction
coefficient k) of the Mo--FeSi.sub.2 metasemi were calculated for
the obtained sample from the measurement data with a spectroscopic
ellipsometer and the reflectance property and transmittance
property measured with a spectrophotometer.
[0054] The calculated multilayer film approximation based on the
optical constants (n, k) for Mo--FeSi.sub.2 metasemi was used to
calculate the absorption rate of the Mo--FeSi.sub.2 metasemi
monolayer film (corresponding to a film thickness of 30 nm). FIG. 3
shows the results for the absorption properties of a Mo--FeSi.sub.2
metasemi monolayer film.
Example 3
[0055] The absorption properties of a heat conversion member of the
present invention were evaluated using an Cu--FeSi.sub.2 metasemi
monolayer film.
[Method of Forming Cu--FeSi.sub.2 Metasemi Monolayer Film]
[0056] On a quartz substrate heated to a temperature no higher than
700.degree. C., FeSi.sub.2 and Cu (copper) were simultaneously
sputtered to form a film. A Cu--FeSi.sub.2 metasemi sample with a
Cu (copper) addition rate of 8.1 vol % was prepared.
[0057] The optical constants (refractive index n, extinction
coefficient k) of the Cu--FeSi.sub.2 metasemi were calculated for
the obtained sample from the measurement data with a spectroscopic
ellipsometer and the reflectance property and transmittance
property measured with a spectrophotometer.
[0058] The calculated multilayer film approximation based on the
optical constants (n, k) for Cu--FeSi.sub.2 metasemi was used to
calculate the absorption rate of the Cu--FeSi.sub.2 metasemi
monolayer film (corresponding to a film thickness of 30 nm). FIG. 4
shows the results for the absorption properties of a Cu--FeSi.sub.2
metasemi monolayer film.
Comparative Example 1
[0059] The absorption properties of a FeSi.sub.2 monolayer film
were evaluated.
[Method of Forming FeSi.sub.2 Monolayer Film]
[0060] On a quartz substrate heated to a temperature no higher than
700.degree. C., FeSi.sub.2 was sputtered to form a film. A
FeSi.sub.2 sample was fabricated.
[0061] The optical constants (refractive index n, extinction
coefficient k) of the FeSi.sub.2 were calculated for the obtained
sample from the measurement data with a spectroscopic ellipsometer
and the reflectance property and transmittance property measured
with a spectrophotometer.
[0062] The calculated multilayer film approximation based on the
optical constants (n, k) for FeSi.sub.2 was used to calculate the
absorption rate of the FeSi.sub.2 monolayer film (corresponding to
a film thickness of 30 nm). FIG. 2 to FIG. 4 show the results for
the absorption properties of a FeSi.sub.2 monolayer film.
<Evaluation Results>
[0063] Referring to FIG. 2, it is seen that the absorption property
curve shifts toward the long wavelength end as the amount of Ag
(silver) addition increases (0 vol %.fwdarw.4.0 vol %.fwdarw.8.6
vol %). Thus, since the sunlight absorption property of the
Ag--FeSi.sub.2 metasemi monolayer film can be varied by adjusting
the Ag (silver) material content (amount of addition), it is
possible to increase the optical selectivity and accomplish
efficient conversion of light to heat.
[0064] Referring to FIG. 3, it is seen that the absorption property
curve shifts toward the long wavelength end as the amount of Mo
(molybdenum) addition increases (0 vol %.fwdarw.4.2 vol
%.fwdarw.9.4 vol %). Thus, since the sunlight absorption property
of the Mo--FeSi.sub.2 metasemi monolayer film can be varied by
adjusting the Mo (molybdenum) material content (amount of
addition), it is possible to increase the optical selectivity and
accomplish efficient conversion of light to heat.
[0065] Referring to FIG. 4, it is seen that the absorption property
curve shifts toward the long wavelength end as the amount of Cu
(copper) addition increases (0 vol %.fwdarw.8.1 vol %). Thus, since
the sunlight absorption property of the Cu--FeSi.sub.2 metasemi
monolayer film can be varied by adjusting the Cu (copper) material
content (amount of addition), it is possible to increase the
optical selectivity and accomplish efficient conversion of light to
heat. Thus, the absorption property curve can be shifted toward the
long wavelength end compared to a FeSi.sub.2 monolayer film, as
shown in FIGS. 2 to 4, and optical selectivity is maintained even
after shifting. It is therefore possible to use the heat conversion
member of the present invention in place of a FeSi.sub.2 monolayer
film. In this case, the heat conversion member of the present
invention may be laminated on a metal layer as an infrared
ray-reflective layer, and a transparent dielectric layer may be
additionally formed as an anti-reflection layer.
Example 4
[0066] The properties of a laminate of the present invention were
evaluated.
[0067] The properties of a laminate prepared by laminating a metal
layer, a metasemi layer (photoabsorbing layer) and a transparent
dielectric layer in that order were evaluated by calculating the
absorption rate using multilayer film approximation, in the same
manner, and a shift in properties toward the long wavelength end
was confirmed, similar to a monolayer film.
REFERENCE SIGNS LIST
[0068] 1 Heat conversion laminate [0069] 11 Transparent dielectric
layer [0070] 12 Layer comprising heat conversion member
(photoabsorbing layer) [0071] 13 Metal layer [0072] 121 Metal fine
particles [0073] 122 Semiconductor
* * * * *