Component for thermoelectric conversion module, thermoelectric conversion module, and method for manufacturing component for thermoelectric conversion module

Abstract

The present application provides a thermoelectric conversion module component having high bonding properties between a thermoelectric conversion layer and an anti-diffusion layer and excellent heat resistance. The thermoelectric conversion module component is a thermoelectric conversion module component having a thermoelectric conversion layer and an anti-diffusion layer in contact with the thermoelectric conversion layer, the thermoelectric conversion layer is a layer containing a thermoelectric conversion material having a silicon element or a tellurium element, the anti-diffusion layer is a layer containing a metal and a thermoelectric conversion material that is the same as the thermoelectric conversion material contained in the thermoelectric conversion layer, and the amount of the thermoelectric conversion material in the anti-diffusion layer is 10 to 50 parts by weight relative to 100 parts by weight of the metal.

Description

Technical Field

[0001] The present invention relates to a thermoelectric conversion module component, a thermoelectric conversion module, and a method for manufacturing the thermoelectric conversion module component. Background Art

[0002] As a module for effectively utilizing thermal energy, the following thermoelectric conversion module is known: a pair of electrodes is formed, one of the electrodes is maintained at a high temperature and the other is maintained at a low temperature to generate a temperature difference, and the Seebeck effect that generates an electromotive force corresponding to the temperature difference is used to convert heat into electricity.

[0003] Generally, a thermoelectric conversion module has a pair of electrodes and a thermoelectric conversion layer disposed between the electrodes, and is used in a high temperature environment. Therefore, mutual material diffusion and heat resistance between the thermoelectric conversion layer and the electrodes become problems. In order to solve such problems, the introduction of an anti-diffusion layer is being studied.

[0004] For example, Patent Document 1 discloses a thermoelectric conversion module including an electrode layer, a thermoelectric conversion layer, and a diffusion prevention layer containing only a metal such as Ni.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 10-74986 Summary of the invention

[0008] Problems to be solved by the invention

[0009] However, in the thermoelectric conversion module described in Patent Document 1, the bonding property and heat resistance between the thermoelectric conversion layer and the diffusion prevention layer are not sufficient.

[0010] Therefore, an object of the present invention is to provide a thermoelectric conversion module member having high bonding properties between a thermoelectric conversion layer and a diffusion prevention layer and excellent heat resistance.

[0011] Means to solve the problem

[0012] That is, the present invention provides the following [1] to [5].

[0013] [1] A thermoelectric conversion module component comprising a thermoelectric conversion layer and a diffusion prevention layer in contact with the thermoelectric conversion layer,

[0014] The thermoelectric conversion layer is a layer containing a thermoelectric conversion material having a silicon element or a tellurium element.

[0015] The diffusion prevention layer is a layer containing a metal and the same thermoelectric conversion material as the thermoelectric conversion material contained in the thermoelectric conversion layer.

[0016] The amount of the thermoelectric conversion material in the anti-diffusion layer is 10 to 50 parts by weight relative to 100 parts by weight of the metal.

[0017] [2] The component for a thermoelectric conversion module according to [1], wherein the thermoelectric conversion material is at least one material selected from the group consisting of materials having, at 25°C, a crystal structure belonging to the space group R-3m and having Bi2Te 3-x Se x (0 < x < 3) as the main phase, materials having, at 25°C, a crystal structure belonging to the space group R-3m and having Bi 2-y Sb y Te3 (0 ≤ y ≤ 2) as the main phase, materials having, at 25°C, a crystal structure belonging to the space group R3m and having GeTe as the main phase, materials having, at 25°C, a crystal structure belonging to the space group R-3m and having GeBi2Te4 as the main phase, materials having, at 25°C, a crystal structure belonging to the space group P-3m1 and having GeBi4Te7 as the main phase, materials having, at 25°C, a crystal structure belonging to the space group Fm-3m and having SnTe as the main phase, materials having, at 25°C, a crystal structure belonging to the space group Fm-3m and having PbTe as the main phase, materials having, at 25°C, a crystal structure of CaF2 type and having Mg2Si 1-z Sn z (0 ≤ z < 1) as the main phase, materials having, at 25°C, a crystal structure belonging to the space group Cmca and having FeSi2 as the main phase, materials having, at 25°C, a crystal structure of chimney-ladder type and having MnSi γ (1.7 ≤ γ ≤ 1.8) as the main phase, and materials having, at 25°C, a crystal structure of B20 type and having CoSi as the main phase.

[0018] [3] A thermoelectric conversion module includes a pair of electrodes and the component for a thermoelectric conversion module according to [1] or [2] disposed between the pair of electrodes.

[0019] [4] The method for manufacturing the component for a thermoelectric conversion module is a method for manufacturing a component for a thermoelectric conversion module having a thermoelectric conversion layer and an anti-diffusion layer in contact with the thermoelectric conversion layer,

[0020] The manufacturing method includes a first step, a second step, and a sintering step,

[0021] In the first step, a first layer is formed by disposing one of the following materials (1) and (2) or a sintered body thereof in a forming die.

[0022] In the second step, the other of the material (1) and the material (2) or a sintered body thereof is arranged in the molding die so as to contact the first layer formed in the first step, thereby forming a second layer to obtain a laminated body;

[0023] In the sintering step, the thermoelectric conversion module component is obtained by sintering the laminated body obtained in the second step.

[0024] Material (1): A thermoelectric conversion material containing silicon or tellurium,

[0025] Material (2): A composition containing a metal and the same thermoelectric conversion material as the material (1) in a ratio of 10 to 50 parts by weight of the thermoelectric conversion material to 100 parts by weight of the metal.

[0026] [5] According to the manufacturing method described in [4], the second step also includes the following step: by arranging the material (1) and the material (2) that is the same as the first layer or its sintered body on the opposite side of the first layer in a manner that is in contact with the second layer, a third layer is formed to obtain a stacked body.

[0027] Effects of the Invention

[0028] According to the present invention, it is possible to provide a thermoelectric conversion module member having high bonding properties between a thermoelectric conversion material layer and a diffusion prevention layer and excellent heat resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029]

Figure 1

[0030]

Figure 2

[0031]

Figure 3

[0032] Reference numerals

[0033] 1: Components for thermoelectric conversion modules (a)

[0034] 1-a: Components for p-type thermoelectric conversion modules

[0035] 1-b: Components for n-type thermoelectric conversion modules

[0036] 2. 2-a, 2-b: Diffusion-proof layer

[0037] 3: Thermoelectric conversion layer

[0038] 3-a: p-type thermoelectric conversion layer

[0039] 3-b: n-type thermoelectric conversion layer

[0040] 4-a: High temperature side electrode

[0041] 4-b, 4-b': Low temperature side electrode

[0042] 5-b, 5-c: Thermoelectric conversion module

[0043] 6: External load

[0044] 7, 8: Wiring

[0045] Next, the embodiments of the present invention will be described in further detail. In addition, the drawings referred to are only to roughly show the shapes, sizes and configurations of the components to the extent that the invention can be understood. The present invention is not limited by the following description, and the components can be appropriately changed within the scope of the purpose of the present invention. In addition, the configuration of the embodiments of the present invention may not be manufactured or used with the configuration shown in the drawings. DETAILED DESCRIPTION

[0046] In this specification, various parameters of the thermoelectric conversion material contained in the thermoelectric conversion layer are represented by the following formulas (1) and (2).

[0047] The maximum thermal efficiency η of thermoelectric conversion materials opt It is represented by the following formula (1). In the following formula (1), T H is the high temperature end temperature [unit: K], T C is the low temperature end temperature [unit: K], T ave T H and T C ] and Z is the average [unit: K] of the thermoelectric conversion performance index z of the thermoelectric conversion material in the temperature range used [unit: 1 / K].

[0048] [Mathematical formula 1]

[0049]

[0050] The thermoelectric conversion performance index z [unit: 1 / K] of a thermoelectric conversion material at a certain temperature T [unit: K] is expressed by the following formula (2). Here, the Seebeck coefficient α [unit: V / K], the resistivity ρ [unit: Ω·m], and the thermal conductivity κ [unit: W / (m·K)] at a certain temperature T.

[0051] [Mathematical formula 2]

[0052]

[0053] The larger the physical property value zT of the thermoelectric conversion material, the higher the maximum thermal efficiency η obtained by thermoelectric conversion. opt To improve the thermal efficiency, it is desirable to obtain a high thermoelectric conversion performance index z in a wide temperature range.

[0054] <Component for thermoelectric conversion module>

[0055] The component for a thermoelectric conversion module of the present invention is a component for a thermoelectric conversion module having a thermoelectric conversion layer and a diffusion prevention layer in contact with the thermoelectric conversion layer. The component for a thermoelectric conversion module may also have two or more layers of the thermoelectric conversion layer or the diffusion prevention layer, respectively.

[0056] <Thermoelectric conversion layer>

[0057] The thermoelectric conversion layer included in the component for a thermoelectric conversion module of the present invention is a layer containing a thermoelectric conversion material having a silicon element or a tellurium element.

[0058] As the thermoelectric conversion material, it is preferably at least one material selected from the group consisting of the following materials. At 25 °C, Bi2Te having a crystal structure belonging to the space group R-3m 3-x Se x (0 < x < 3) as the main phase material, Bi having a crystal structure belonging to the space group R-3m 2-y Sb y Te3 (0 ≤ y ≤ 2) as the main phase material, GeTe having a crystal structure belonging to the space group R3m as the main phase material, GeBi2Te4 having a crystal structure belonging to the space group R-3m as the main phase material, GeBi4Te7 having a crystal structure belonging to the space group P-3m1 as the main phase material, SnTe having a crystal structure belonging to the space group Fm-3m as the main phase material, PbTe having a crystal structure belonging to the space group Fm-3m as the main phase material, Mg2Si having a CaF2-type crystal structure 1-z Sn z (0 ≤ z < 1) as the main phase material, FeSi2 having a crystal structure belonging to the space group Cmca as the main phase material, MnSi having a chimney-ladder type crystal structure γ (1.7 ≤ γ ≤ 1.8) as the main phase material, and CoSi having a B20-type crystal structure as the main phase material.

[0059] The thermoelectric conversion material is a semiconductor. A thermoelectric conversion material in which the carriers are electrons is called an n-type thermoelectric conversion material, and a thermoelectric conversion material in which the carriers are holes is called a p-type thermoelectric conversion material. The thermoelectric conversion material may contain an element (sometimes referred to as a doping element in this specification) that increases the carrier density of electrons or holes in the thermoelectric conversion material. Depending on the type of doping element contained in the thermoelectric conversion material, it can become an n-type thermoelectric conversion material or a p-type thermoelectric conversion material.

[0060] As a doping element contained in the n-type thermoelectric conversion material, I can be cited. As a doping element contained in the p-type thermoelectric conversion material, Na can be cited.

[0061] As an n-type thermoelectric conversion material, a material with a crystal structure Bi2Te 3-x Se x (0 < x < 3) as the main phase can be cited.

[0062] As a p-type thermoelectric conversion material with holes as carriers, a material with a crystal structure of Bi 2-y Sb y Te3(0 ≤ y ≤ 2) as the main phase and a material with a crystal structure of MnSi γ (1.7 ≤ γ ≤ 1.8) as the main phase can be cited.

[0063] As a thermoelectric conversion material that can become either an n-type thermoelectric conversion material or a p-type thermoelectric conversion material depending on the type of doping element contained in the thermoelectric conversion material, a material with a crystal structure of GeTe belonging to the space group R3m as the main phase, a material with a crystal structure of GeBi2Te4 belonging to the space group R-3m as the main phase, a material with a crystal structure of GeBi4Te7 belonging to the space group P-3m1 as the main phase, a material with a crystal structure of SnTe belonging to the space group Fm-3m as the main phase, a material with a crystal structure of PbTe belonging to the space group Fm-3m as the main phase, a material with a crystal structure of Mg2Si 1-z Sn z (0 ≤ z < 1) as the main phase, a material with a crystal structure of FeSi2 belonging to the space group Cmca as the main phase, and a material with a crystal structure of CoSi belonging to the B20 type as the main phase can be cited.

[0064] With a crystal structure of Bi2Te belonging to the space group R-3m 3-x Se xThe material with (0 < x < 3) as the main phase may contain elements other than Bi, Te, and Se that constitute the main phase, and may contain two or more kinds. As elements other than Bi, Te, and Se, sulfur element or halogen element may also be contained. As the halogen element, from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the component for a thermoelectric conversion module of the present invention, I, Br, or Cl is preferred.

[0065] From the viewpoint of the heat resistance of the component for a thermoelectric conversion module, when the amount of Bi contained in the material with Bi2Te 3-x Se x as the main phase is set to 100 mol%, for Bi2Te 3- x Se x (0 < x < 3) as the main phase, the content of elements other than Bi, Te, and Se is preferably 10 mol% or less for each element, and more preferably 5 mol% or less.

[0066] For Bi with a crystal structure belonging to the space group R-3m 2-y Sb y Te3 (0 ≤ y ≤ 2) as the main phase, the material may contain elements other than Bi, Sb, and Te that constitute the main phase, and may contain two or more kinds. As elements other than Bi, Sb, and Te, alkali metal elements and alkaline earth metal elements may also be contained. As the alkali metal element, Li, Na, or K can be cited, and as the alkaline earth metal element, Mg, Ca, or Ba can be cited. From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the component for a thermoelectric conversion module of the present invention, it is preferred to contain Mg or Ca.

[0067] From the viewpoint of the heat resistance of the component for a thermoelectric conversion module, when the amount of Bi contained in the material with Bi 2-y Sb y Te3 as the main phase is set to 100 mol%, for Bi 2- y Sb y Te3 (0 ≤ y ≤ 2) as the main phase, the content of elements other than Bi, Sb, and Te is preferably 10 mol% or less for each element, and more preferably 5 mol% or less.

[0068] The material having GeTe as the main phase having a crystal structure belonging to the space group R3m may contain elements other than Ge and Te constituting the main phase, or may contain two or more. As elements other than Ge and Te, Group 14 elements, Group 15 elements, Group 16 elements or transition metal elements may also be contained. As Group 14 elements, Pb, Sn or Si may be cited, and from the viewpoint of being able to reduce lattice thermal conductivity, Pb or Sn is preferred. As Group 15 elements, As, Bi or Sb may be cited, and from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, Bi or Sb is preferably contained. As Group 16 elements, S or Se may be cited, and from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, Se is preferably contained. As transition metal elements, Ti, Cr, Mn, Fe, Co, Ni, Cu, Mo, Rh, Ag or Hf can be mentioned. From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, Cu or Ag is preferably contained.

[0069] From the viewpoint of heat resistance of components for thermoelectric conversion modules, when the amount of Te contained in a material having GeTe as the main phase is set to 100 mol%, the content of elements other than Ge and Te contained in the material having GeTe as the main phase having a crystal structure belonging to the space group R3m is preferably 30 mol% or less for each element, and more preferably 20 mol% or less.

[0070] When the material having GeTe as the main phase and a crystal structure belonging to the space group R3m contains two or more elements other than Ge and Te, from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, it is preferred to select at least two elements from the group consisting of Sb, Ag, Bi and Cu.

[0071] When the elements other than Ge and Te contained in the material with GeTe as the main phase having a crystal structure belonging to the space group R3m are Bi and Cu, from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, when the amount of Te contained in the material with GeTe as the main phase is set to 100 mol%, the content of Bi or Cu is preferably less than 20 mol%, more preferably less than 10 mol%, and the longest diameter of the crystals of Bi and Cu contained in the material is preferably less than 2.0 μm.

[0072] The material having GeBi2Te4 as the main phase and having a crystal structure belonging to the space group R-3m may contain elements other than Ge, Bi and Te constituting the main phase.

[0073] The material having GeBi4Te7 as the main phase and having a crystal structure belonging to the space group P-3m1 may also contain elements other than Ge, Bi and Te constituting the main phase. Elements other than Ge, Bi and Te may include Cu or Sb.

[0074] From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the components for the thermoelectric conversion module of the present invention, when the amount of Ge contained in the material with GeBi4Te7 as the main phase is set to 100 mol%, the content of elements other than Ge, Bi and Te contained in the material with GeBi4Te7 as the main phase having a crystal structure belonging to the space group P-3m1 is preferably a Cu content of less than 0.20 mol%, and a Sb content of less than 50 mol%.

[0075] The material having SnTe as the main phase and having a crystal structure belonging to the space group Fm-3m may contain elements other than Sn and Te constituting the main phase, or may contain two or more elements. Se or I may be included as elements other than Sn and Te.

[0076] From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the components for the thermoelectric conversion module of the present invention, when the amount of Sn contained in the material with SnTe as the main phase is set to 100 mol%, the content of elements other than Sn and Te contained in the material with SnTe as the main phase having a crystal structure belonging to the space group Fm-3m is preferably Se is less than 30 mol%, and more preferably I is less than 5 mol%.

[0077] The material having PbTe as the main phase and having a crystal structure belonging to the space group Fm-3m may contain elements other than Pb and Te constituting the main phase, or may contain two or more elements. As elements other than Pb and Te, Na or I may be included.

[0078] From the perspective of heat resistance of components for thermoelectric conversion modules, when the amount of Pb contained in the material with PbTe as the main phase is set to 100 mol%, the content of Na element contained in the material with PbTe as the main phase having a crystal structure belonging to the space group Fm-3m is preferably less than 5 mol%.

[0079] From the perspective of heat resistance of components for thermoelectric conversion modules, when the amount of Pb contained in a material with PbTe as the main phase is set to 100 mol%, the content of the I element contained in a material with PbTe as the main phase having a crystal structure belonging to the space group Fm-3m is preferably less than 1 mol%.

[0080] Mg2Si having the CaF2 type crystal structure1-z Sn z The material of the main phase (0≤z<1) may contain elements other than Mg, Si and Sn constituting the main phase, or may contain two or more elements. As elements other than Mg, Si and Sn, Bi, Sb, Te or Ge may be included.

[0081] From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, in the case of Mg2Si 1-z Sn z When the amount of Mg contained in the material having the main phase (0≤z<1) is set to 100 mol %, the Mg2Si 1-z Sn z The content of elements other than Mg, Si and Sn contained in the material of the main phase (0≤z<1) is preferably 20 mol % or less, more preferably 10 mol % or less per element.

[0082] The material having FeSi2 having a crystal structure belonging to the space group Cmca as the main phase may contain elements other than Fe and Si constituting the main phase, or may contain two or more elements. Cr and Co may also be included as elements other than Fe and Si.

[0083] From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the components for the thermoelectric conversion module of the present invention, when the amount of Fe contained in the material with FeSi2 as the main phase is set to 100 mol%, the content of elements other than Fe and Si contained in the material with FeSi2 as the main phase having a crystal structure belonging to the space group Cmca is preferably 10 mol% or less for each element.

[0084] MnSi having the chimney-ladder crystal structure γ The material with (1.7≤γ≤1.8) as the main phase may contain elements other than Mn and Si constituting the main phase, or may contain two or more elements. As elements other than Mn and Si, Al, Ge, Cr or Fe may be contained.

[0085] From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, in γ When the amount of Mn contained in the material having (1.7≤γ≤1.8) as the main phase is 100 mol %, the MnSi having the chimney-ladder crystal structure γ The content of elements other than Mn and Si contained in the material having (1.7≤γ≤1.8) as the main phase is preferably 20 mol % or less, more preferably 10 mol % or less per element.

[0086] The material with CoSi having the B20 type crystal structure as the main phase may contain elements other than Co and Si constituting the main phase, or may contain two or more elements. As elements other than Co and Si, Al, Ni, Pd, Pt or Cu may also be contained. The material with CoSi having the B20 type crystal structure as the main phase becomes an n-type thermoelectric conversion material when Ni or Pd is contained as a doping element, and becomes a p-type thermoelectric conversion material when Al is contained as a doping element.

[0087] From the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the components for the thermoelectric conversion module of the present invention, when the amount of Co contained in the material with CoSi as the main phase is set to 100 mol%, the content of elements other than Co and Si contained in the material with CoSi as the main phase having the B20 type crystal structure is preferably 10 mol% or less for each element.

[0088] As the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention, from the viewpoint of heat resistance and durability, preferably at 25°C, a material having a GeTe with a crystal structure belonging to the space group R3m as the main phase, a material having a GeBi2Te4 with a crystal structure belonging to the space group R-3m as the main phase, a material having a GeBi4Te7 with a crystal structure belonging to the space group P-3m1 as the main phase, a material having a SnTe with a crystal structure belonging to the space group Fm-3m as the main phase, a material having a CaF2 type crystal structure as the main phase, a material having a GeTe with a crystal structure belonging to the space group Fm-3m ... 1-z Sn z (0≤z<1) as the main phase, MnSi with a chimney-ladder crystal structure γ (1.7≤γ≤1.8) as the main phase, more preferably GeTe as the main phase having a crystal structure belonging to the space group R3m, MnSi as the main phase having a chimney-ladder crystal structure γ (1.7≤γ≤1.8) as the main phase, Ge 0.95 Bi 0.05 Cu 0.03 Te、MnSi 1.73 .

[0089] The thermoelectric conversion material in the thermoelectric conversion layer may contain one kind alone or two or more kinds.

[0090] The thermoelectric conversion layer of the thermoelectric conversion module component of the present invention may contain "other materials other than the thermoelectric conversion material" which are not thermoelectric conversion materials. Examples of such materials include A l2 Oxides such as O3, SiO2, etc.

[0091] The material other than the thermoelectric conversion material in the thermoelectric conversion layer may be contained alone or in combination of two or more.

[0092] The content of the thermoelectric conversion material in the thermoelectric conversion layer of the thermoelectric conversion module component of the present invention is preferably 95 mass % or more from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention when the total amount of all compounds in the thermoelectric conversion layer is set to 100 mass %.

[0093] The "other materials other than thermoelectric conversion materials" in the thermoelectric conversion layer of the thermoelectric conversion module component of the present invention is preferably 5 mass % or less from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention when the total amount of all compounds in the thermoelectric conversion layer is set to 100 mass %.

[0094] The film thickness of the thermoelectric conversion layer is not particularly limited. From the perspective of improving the thermoelectric conversion efficiency of the thermoelectric conversion module of the present invention, it is preferably 100 μm or more, more preferably 500 μm or more, and further preferably 1000 μm or more. From the perspective of excellent mechanical durability, it is preferably 5 cm or less, more preferably 2 cm or less, and further preferably 1 cm or less. The upper limit and the lower limit may be arbitrarily combined.

[0095] <Diffusion-proof layer>

[0096] The diffusion prevention layer included in the thermoelectric conversion module member of the present invention is a layer containing a metal and the same thermoelectric conversion material as that contained in the thermoelectric conversion layer.

[0097] The thermoelectric conversion material in the diffusion prevention layer may contain one kind alone or two or more kinds.

[0098] In the diffusion prevention layer, the amount of the thermoelectric conversion material is 10 to 50 parts by weight, preferably 11 to 45 parts by weight, more preferably 25 to 45 parts by weight, and particularly preferably 35 to 43 parts by weight, based on 100 parts by weight of the metal.

[0099] Examples of the metal contained in the diffusion prevention layer included in the thermoelectric conversion module member of the present invention include Al or a transition metal, and a transition metal is preferred from the viewpoint of the bonding property between the thermoelectric conversion layer and the diffusion prevention layer.

[0100] Among the transition metals, a transition metal having a melting point of 500°C or more is preferred, a 3d transition metal, a 4d transition metal or Ta is more preferred, a 3d transition metal or a 4d transition metal is further preferred, and a 3d transition metal (especially Ni) is particularly preferred. As the 3d transition metal, for example, Ti, V, Cr, Mn, Fe, Co, Ni or Cu can be cited, preferably Mn, Fe, Co, Ni or Cu, more preferably Fe, Co or Ni. As the 4d transition metal, for example, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd or Ag can be cited, preferably Nb, Mo, Pd or Ag.

[0101] The metal contained in the diffusion prevention layer may be an alloy composed of different types of metals. Among them, an alloy composed of a transition metal is preferred, and an alloy composed of a 3d transition metal is more preferred. Specifically, Cr-Ni, Co-Fe, Fe-Cr, Fe-Ni or Ni-Co alloys may be cited.

[0102] The metal in the diffusion prevention layer may contain one kind alone or two or more kinds.

[0103] The thermoelectric conversion material and the metal in the diffusion prevention layer preferably form a sea-island phase separation structure.

[0104] The sea-island phase separation structure is a phase separation structure having sea-like regions of thermoelectric conversion material and island-like regions of metal that are immiscible with each other.

[0105] The sea-like region of the thermoelectric conversion material is a region where the thermoelectric conversion material exists, and the island-like metal region is a region where particles of the metal or aggregates of the particles exist (hereinafter sometimes referred to as an island phase).

[0106] With such a structure, the bonding property between the thermoelectric conversion layer and the diffusion prevention layer is improved.

[0107] As a method for observing the sea-island phase separation structure, for example, a method of observing the cross section of the diffusion prevention layer using a scanning electron microscope (SEM) can be cited. In addition, information about the composition can be obtained by the following method, which is a method of performing elemental analysis or composition analysis by detecting characteristic X-rays generated by electron beam irradiation and splitting them according to energy, namely SEM-EDX method (Energy Dispersive X-ray Spectroscopy).

[0108] The shape of the island phase is spherical or deformed spherical, etc., without particular limitation. The metal constituting the island phase is preferably in a particle form. By being in a particle form, it is easy to form the island phase separation structure, and the bonding between the thermoelectric conversion layer and the diffusion prevention layer of the thermoelectric conversion module component of the present invention is improved. The particle size of the metal is not particularly limited, preferably 200 μm or less, more preferably 150 μm or less.

[0109] There is no particular restriction on the film thickness of the diffusion prevention layer. From the viewpoint of improving the bonding between the thermoelectric conversion layer and the diffusion prevention layer possessed by the thermoelectric conversion module component of the present invention, it is preferably from 100 μm to 5000 μm, more preferably from 200 μm to 2000 μm, and particularly preferably from 250 μm to 1000 μm.

[0110] As "other components" other than the metal and the thermoelectric conversion material in the diffusion prevention layer, oxides other than the thermoelectric conversion material may be included, such as Al2O3 and SiO2. The diffusion prevention layer may contain oxides other than the thermoelectric conversion material, thereby increasing the hardness of the thermoelectric conversion material module component.

[0111] The other components in the diffusion prevention layer may be contained alone or in combination of two or more.

[0112] The "other materials" in the diffusion prevention layer of the thermoelectric conversion module component of the present invention are preferably 5% by mass or less when the total amount of all compounds in the diffusion prevention layer is set to 100% by mass, from the viewpoint of improving the physical property value zT of the thermoelectric conversion material contained in the thermoelectric conversion module component of the present invention.

[0113] <Components for thermoelectric conversion modules>

[0114] The thermoelectric conversion module component of the present invention comprises at least one thermoelectric conversion layer and at least one diffusion prevention layer, and the layers are in contact with each other.

[0115] In the thermoelectric conversion module component of the present invention, when there are two or more thermoelectric conversion layers and two or more diffusion prevention layers, the thermoelectric conversion material contained in at least one thermoelectric conversion layer is the same as the thermoelectric conversion material contained in at least one diffusion prevention layer in contact with the thermoelectric conversion layer. In addition, in the thermoelectric conversion module component of the present invention, when there are two or more thermoelectric conversion materials contained in the thermoelectric conversion layer and / or the diffusion prevention layer, at least one thermoelectric conversion material contained in the thermoelectric conversion layer is the same as the at least one thermoelectric conversion material contained in the diffusion prevention layer in contact with the thermoelectric conversion layer.

[0116] Figure 1This is a schematic cross-sectional view showing the structure of a thermoelectric conversion module component (a) as one embodiment of the present invention. This thermoelectric conversion module component is a laminated body in which a diffusion prevention layer 2 and a thermoelectric conversion layer 3 are adjacently bonded in this order.

[0117] In other embodiments of the present invention, the thermoelectric conversion module component (b) is a laminated body formed by adjacently bonding an anti-diffusion layer, a thermoelectric conversion layer, and an anti-diffusion layer in this order. In this case, the two anti-diffusion layers adjacent to the thermoelectric conversion layer may be the same or different from each other, as long as the thermoelectric conversion material contained in the thermoelectric conversion layer is the same as the thermoelectric conversion material contained in at least one anti-diffusion layer in contact with the thermoelectric conversion layer.

[0118] In another embodiment of the present invention, the thermoelectric conversion module component (c) is a laminate formed by adjoining a diffusion prevention layer, a thermoelectric conversion layer, and a thermoelectric conversion layer in this order. At this time, the two adjacent thermoelectric conversion layers may be the same as or different from each other. When the thermoelectric conversion materials in the two thermoelectric conversion layers are different from each other, the thermoelectric conversion material contained in the diffusion prevention layer and the thermoelectric conversion material contained in the thermoelectric conversion layer in contact with the diffusion prevention layer are the same.

[0119] In another embodiment of the present invention, the thermoelectric conversion module component (d) is a laminate formed by adjacently bonding a thermoelectric conversion layer, an anti-diffusion layer, and a thermoelectric conversion layer in this order. The two thermoelectric conversion layers adjacent to the anti-diffusion layer may be the same or different from each other. When the thermoelectric conversion materials in the two thermoelectric conversion layers are different from each other, as long as the thermoelectric conversion material in the anti-diffusion layer is the same as the thermoelectric conversion material contained in at least one of the two thermoelectric conversion layers in contact with the anti-diffusion layer, the thermoelectric conversion material in the anti-diffusion layer may also be a thermoelectric conversion material that is arbitrarily mixed with the thermoelectric conversion materials contained in the two thermoelectric conversion layers.

[0120] In another embodiment of the present invention, the thermoelectric conversion module component (e) is a laminate formed by adjacently bonding a thermoelectric conversion layer, an anti-diffusion layer, and an anti-diffusion layer in this order. Two adjacent anti-diffusion layers can be the same or different from each other, as long as the thermoelectric conversion material contained in the thermoelectric conversion layer is the same as the thermoelectric conversion material contained in the anti-diffusion layer in contact with the thermoelectric conversion layer. In the two anti-diffusion layers, when the content of the thermoelectric conversion material in the anti-diffusion layer in contact with the thermoelectric conversion layer is higher than the content of the thermoelectric conversion material in the other anti-diffusion layer, the thermoelectric conversion module having the thermoelectric conversion module component (e) is difficult to produce peeling caused by heating due to the change in the linear thermal expansion coefficient, and the bonding between the layers is improved.

[0121] In other embodiments of the present invention, the thermoelectric conversion module component (f) is a laminate formed by adjacently bonding a thermoelectric conversion layer, an anti-diffusion layer, a thermoelectric conversion layer, an anti-diffusion layer, and a thermoelectric conversion layer in this order. The two anti-diffusion layers may be the same or different from each other. The three thermoelectric conversion layers may be the same or different from each other. In the three thermoelectric conversion layers, when the thermoelectric conversion materials in the two thermoelectric conversion layers in contact with one of the two anti-diffusion layers are different from each other, as long as the thermoelectric conversion material in the anti-diffusion layer is the same as the thermoelectric conversion material contained in the thermoelectric conversion layer that is only in contact with the anti-diffusion layer of the two thermoelectric conversion layers in contact with the anti-diffusion layer, it can also be a thermoelectric conversion material that arbitrarily mixes the thermoelectric conversion materials contained in the two thermoelectric conversion layers in contact with the anti-diffusion layer.

[0122] The thermoelectric conversion module member of the present invention may include layers other than the thermoelectric conversion layer and the diffusion prevention layer.

[0123] <Thermoelectric conversion module>

[0124] The thermoelectric conversion module of the present invention includes a pair of electrodes and the thermoelectric conversion module component provided between the pair of electrodes. In addition, the thermoelectric conversion module of the present invention may include elements other than the pair of electrodes and the thermoelectric conversion module component.

[0125] Figure 2 and Figure 3 This is a schematic cross-sectional view showing the structure of a thermoelectric conversion module as one embodiment of the present invention. Figure 2 In the thermoelectric conversion module 5-b, when the electrode on the heating side (sometimes referred to as the high-temperature side electrode in this specification) 4-a is heated, a potential difference is generated between the electrode on the unheated side (sometimes referred to as the low-temperature side electrode in this specification) 4-b and the high-temperature side electrode 4-a due to the temperature difference. For example, in the case of a p-type thermoelectric conversion material in which the carriers are holes in the thermoelectric conversion material contained in the thermoelectric conversion layer of the thermoelectric conversion module 5-a, the low-temperature side electrode 4-b has a higher potential than the high-temperature side electrode 4-a. At this time, the external load 6 is electrically connected between the high-temperature side electrode 4-a and the low-temperature side electrode 4-b through the wirings 7 and 8, so that the current flows from the wiring 8 via the external load 6 in the direction of the wiring 7.

[0126] In one embodiment of the present invention, the thermoelectric conversion module is a stacked body in which a high temperature side electrode, a diffusion prevention layer, a thermoelectric conversion layer, a thermoelectric conversion layer, and a low temperature side electrode are adjacently bonded in this order. The two thermoelectric conversion layers may be the same or different from each other.

[0127] In one embodiment of the present invention, the thermoelectric conversion module is a laminated body formed by adjoining and bonding a high temperature side electrode, an anti-diffusion layer, a thermoelectric conversion layer, an anti-diffusion layer, a thermoelectric conversion layer, and a low temperature side electrode in this order. The two anti-diffusion layers may be the same or different from each other. The two thermoelectric conversion layers may be the same or different from each other.

[0128] In one embodiment of the present invention, the thermoelectric conversion module is a laminated body formed by adjoining and bonding a high temperature side electrode, an anti-diffusion layer, a thermoelectric conversion layer, an anti-diffusion layer, a thermoelectric conversion layer, an anti-diffusion layer, and a low temperature side electrode in this order. The three anti-diffusion layers may be the same or different from each other. The two thermoelectric conversion layers may be the same or different from each other.

[0129] The pair of electrodes provided in the thermoelectric conversion module of the present invention is not particularly limited, and a metal with high conductivity can be used. For example, Al and transition metals can be mentioned. As the transition metal, 3d transition metals are preferred, and Fe, Cu or Ni is more preferred.

[0130] The pair of electrodes may be made of the same metal or different metals.

[0131] The electrodes and thermoelectric conversion module components of the thermoelectric conversion module of the present invention can also be fixed by solder, brazing or welding. As solder, for example, solder containing In (for example, In-Ga solder), solder containing Pb or solder containing Sn can be cited. As solder for brazing, for example, solder containing Ag, solder containing Pb, solder containing Sn or solder containing Al can be cited.

[0132] In one embodiment of the present invention, the thermoelectric conversion module may be a module in which a plurality of thermoelectric conversion layers are electrically connected via electrodes. Examples of such a thermoelectric conversion module include: Figure 3 Thermoelectric conversion module.

[0133] exist Figure 3 In the thermoelectric conversion module 5-c shown, the p-type thermoelectric conversion module component 1-a and the n-type thermoelectric conversion module component 1-b are arranged in a π-type via the high-temperature side electrode 4-a, and the p-type thermoelectric conversion module component 1-a has a p-type thermoelectric conversion layer 3-a and an anti-diffusion layer 2-a using a p-type thermoelectric conversion material with holes as carriers, and the n-type thermoelectric conversion module component 1-b has an n-type thermoelectric conversion layer 3-b and an anti-diffusion layer 2-b using an n-type thermoelectric conversion material with electrons as carriers. Figure 3When the high temperature side electrode 4-a side of the thermoelectric conversion module 5-c is connected, the low temperature side electrode 4-b is at a higher potential than the low temperature side electrode 4-b' due to the temperature difference. At this time, the external load 6 is electrically connected between the low temperature side electrode 4-b and the low temperature side electrode 4-b' by using the wiring 7 and the wiring 8, so that the current flows from the wiring 8 through the external load 6 to the wiring 7 direction.

[0134] <Method for manufacturing thermoelectric conversion module component>

[0135] The method for manufacturing a thermoelectric conversion module component of the present invention is a method for manufacturing the thermoelectric conversion module component, which is a method for manufacturing a thermoelectric conversion module component comprising a thermoelectric conversion layer and a diffusion prevention layer in contact with the thermoelectric conversion layer.

[0136] The method comprises a first step, a second step and a sintering step.

[0137] In the first step, the first layer is formed by placing one of the following material (1) and the following material (2) or a sintered body thereof in a molding die;

[0138] In the second step, the other of the material (1) and the material (2) or a sintered body thereof is arranged in the molding die so as to contact the first layer formed in the first step, thereby forming a second layer to obtain a laminated body;

[0139] In the sintering step, the thermoelectric conversion module component is obtained by sintering the laminated body obtained in the second step.

[0140] Material (1): A thermoelectric conversion material containing silicon or tellurium,

[0141] Material (2): A composition containing a metal and the same thermoelectric conversion material as the material (1) in a ratio of 10 to 50 parts by weight of the thermoelectric conversion material to 100 parts by weight of the metal.

[0142] The material (1) is the same as the thermoelectric conversion material containing silicon or tellurium in the thermoelectric conversion layer included in the thermoelectric conversion module member described above.

[0143] In material (1), the average particle size of the thermoelectric conversion material is preferably 100 μm or less, more preferably 50 μm or less. The thermoelectric conversion layer having the thermoelectric conversion material having the average particle size within the above range has low thermal conductivity, and the thermoelectric conversion efficiency of the thermoelectric conversion module having the thermoelectric conversion layer is improved.

[0144] In the material (1), the thermoelectric conversion material may be contained alone or in combination of two or more.

[0145] Material (2) is a composition comprising a metal and a thermoelectric conversion material identical to that of material (1) in a ratio of 10 to 50 parts by weight, preferably 11 to 45 parts by weight, more preferably 25 to 45 parts by weight, and still more preferably 35 to 43 parts by weight of the thermoelectric conversion material to 100 parts by weight of the metal.

[0146] The metal of the material (2) is the same as the metal contained in the diffusion prevention layer provided in the thermoelectric conversion module component described above.

[0147] In the material (2), the metal is preferably in a particle form. The particle size of the metal is not particularly limited, but is preferably 200 μm or less, and more preferably 150 μm or less. By using metal particles, the material (2) can easily form the sea-island phase separation structure as a phase separation structure having a sea-like material (1) region and an island-like metal region. By using such a method for manufacturing a material (2), the thermoelectric conversion module component obtained has improved bonding between the thermoelectric conversion layer and the diffusion prevention layer.

[0148] In the material (2), the thermoelectric conversion material and the metal may be contained in a single type or in a combination of two or more types.

[0149] In material (2), from the viewpoint that material (2) easily forms the sea-island phase separation structure, the particle size of the thermoelectric conversion material of material (1) is preferably 100 μm or less, more preferably 50 μm or less. The thermoelectric conversion module component obtained by the manufacturing method using such material (2) has improved bonding between the thermoelectric conversion layer and the diffusion prevention layer.

[0150] In the material (2), from the viewpoint of heat resistance of the thermoelectric conversion module component, the amount of the thermoelectric conversion material is preferably 11 to 45 parts by weight, more preferably 15 to 45 parts by weight, and particularly preferably 25 to 45 parts by weight relative to 100 parts by weight of the metal. The thermoelectric conversion module component obtained by the method of manufacturing the material (2) in which the ratio of the metal to the thermoelectric conversion material is within this range has improved bonding properties between the thermoelectric conversion layer and the diffusion prevention layer.

[0151] In the material (2), the method for uniformly mixing the metal and the material (1) is not particularly limited, and a method using a ball mill can be mentioned. By pulverizing with a ball mill, a uniform composition can be obtained, and each component can be adjusted to a desired particle size.

[0152] The so-called sintered body is a formed body obtained by sintering.

[0153] As for the sintering treatment, there is no particular limitation, and treatment methods such as hot pressing sintering method and discharge plasma sintering method can be cited. As the hot pressing sintering method, high frequency hot pressing is preferred, and as the discharge plasma sintering method, a discharge plasma sintering method in which an electric current is applied to the object to be treated and sintering is performed by internal heating is preferred. From the viewpoint of obtaining a high-density sintered body, hot pressing sintering method is preferred. In the hot pressing sintering method or the discharge plasma sintering method, when pressurizing, the applied pressure is preferably 30MPa or more. As the sintering temperature, it is preferably implemented at a temperature of 2 / 3 or more of the melting point of the material (1) in absolute thermometer. The sintering time is not particularly limited, and is preferably 5 minutes or more.

[0154] A high-density sintered body can be obtained by such a sintering method, and the thermoelectric conversion module component produced using the sintered body has improved bonding properties between the diffusion prevention layer and the thermoelectric conversion layer.

[0155] The forming die is not particularly limited, and examples thereof include a carbon-made die and punch for spark plasma sintering, or a mold.

[0156] As a method for producing the thermoelectric conversion module member of the present invention, for example, the following production methods (a-1) to (a-4) may be used.

[0157] Manufacturing method (a-1): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, and a sintering step.

[0158] In the first step, a first layer is formed by placing a powder of one of the material (1) and the material (2) in a molding die;

[0159] In the second step, a sintered body of the other of the material (1) and the material (2) is arranged in the mold so as to be in contact with the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0160] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the second step.

[0161] Manufacturing method (a-2): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, and a sintering step.

[0162] In the first step, a first layer is formed by placing a sintered body of one of the material (1) and the material (2) in a forming mold;

[0163] In the second step, a powder of the other of the material (1) and the material (2) is arranged in the mold so as to contact the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0164] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the second step.

[0165] Manufacturing method (a-3): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, and a sintering step.

[0166] In the first step, a first layer is formed by placing a powder of one of the material (1) and the material (2) in a molding die;

[0167] In the second step, a powder of the other of the material (1) and the material (2) is arranged in the mold so as to contact the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0168] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the second step.

[0169] Manufacturing method (a-4): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, and a sintering step.

[0170] In the first step, a first layer is formed by placing a sintered body of one of the material (1) and the material (2) in a forming mold;

[0171] In the second step, a sintered body of the other of the material (1) and the material (2) is arranged in the mold so as to be in contact with the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0172] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the second step.

[0173] The manufacturing method of a component for a thermoelectric conversion module of the present invention may be a manufacturing method which further includes the following step in the second step: among the material (1) and the material (2), the same material as the first layer or its sintered body is arranged on the opposite side of the first layer (i.e., on the opposite side of the second layer when observed from the first layer) in such a manner as to be in contact with the second layer of the stacked body obtained in the second step, thereby forming a third layer and obtaining a stacked body.

[0174] As a method for producing the thermoelectric conversion module member of the present invention, for example, the following production methods (b-1) to (b-8) may be used.

[0175] Manufacturing method (b-1): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step,

[0176] In the first step, a first step of forming a first layer by placing a powder of one of the material (1) and the material (2) in a molding die;

[0177] In the second step, a powder of the other of the material (1) and the material (2) is arranged in the mold so as to contact the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0178] In the third step, a powder of the material (1) or the material (2) is arranged in the mold so as to contact the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0179] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0180] Manufacturing method (b-2): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step,

[0181] In the first step, a first layer is formed by placing a sintered body of one of the material (1) and the material (2) in a forming mold;

[0182] In the second step, a powder of the other of the material (1) and the material (2) is arranged in the mold so as to contact the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0183] In the third step, a powder of the material (1) or the material (2) is arranged in the mold so as to contact the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0184] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0185] Manufacturing method (b-3): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step.

[0186] In the first step, a first layer is formed by placing a powder of one of the material (1) and the material (2) in a molding die;

[0187] In the second step, a sintered body of the other of the material (1) and the material (2) is arranged in the mold so as to be in contact with the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0188] In the third step, a powder of the material (1) or the material (2) is arranged in the mold so as to contact the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0189] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0190] Manufacturing method (b-4): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step,

[0191] In the first step, a first layer is formed by placing a powder of one of the material (1) and the material (2) in a molding die;

[0192] In the second step, a powder of the other of the material (1) and the material (2) is arranged in the mold so as to contact the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0193] In the third step, a sintered body of the material (1) or the material (2) is arranged in the mold so as to be in contact with the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0194] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0195] Manufacturing method (b-5): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step.

[0196] In the first step, a first layer is formed by placing a sintered body of one of the material (1) and the material (2) in a forming mold;

[0197] In the second step, a sintered body of the other of the material (1) and the material (2) is arranged in the mold so as to be in contact with the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0198] In the third step, a powder of the material (1) or the material (2) is arranged in the mold so as to contact the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0199] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0200] Manufacturing method (b-6): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step,

[0201] In the first step, a first layer is formed by placing a sintered body of one of the material (1) and the material (2) in a forming mold;

[0202] In the second step, a powder of the other of the material (1) and the material (2) is arranged in the mold so as to contact the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0203] In the third step, a sintered body of the material (1) or the material (2) is arranged in the mold so as to be in contact with the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0204] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0205] Manufacturing method (b-7): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step,

[0206] In the first step, a first layer is formed by placing a powder of one of the material (1) and the material (2) in a molding die;

[0207] In the second step, a sintered body of the other of the material (1) and the material (2) is arranged in the mold so as to be in contact with the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0208] In the third step, a sintered body of the material (1) or the material (2) is arranged in the mold so as to be in contact with the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0209] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0210] Manufacturing method (b-8): A method for manufacturing a thermoelectric conversion module component, comprising a first step, a second step, a third step and a sintering step,

[0211] In the first step, a first layer is formed by placing a sintered body of one of the material (1) and the material (2) in a forming mold;

[0212] In the second step, a sintered body of the other of the material (1) and the material (2) is arranged in the mold so as to be in contact with the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body;

[0213] In the third step, a sintered body of the material (1) or the material (2) is arranged in the mold so as to be in contact with the second layer of the laminate obtained in the second step, thereby forming a third layer and obtaining a laminate;

[0214] In the sintering step, the thermoelectric conversion module member is obtained by sintering the laminated body obtained in the third step.

[0215] As the manufacturing method of the component for thermoelectric conversion module of the present invention, from the viewpoint of the bonding property between the thermoelectric conversion layer and the diffusion prevention layer, among the manufacturing methods of the component for thermoelectric conversion module consisting of the first step and the second step, the manufacturing methods (a-1) to (a-3), (b-1) to (b-4) or (b-6) are preferred, and the manufacturing method (b-1) is more preferred.

[0216] In the above-mentioned production method, the powder placed in the molding die in the first step and / or the second step may be sintered in the step.

[0217] In the method for producing a thermoelectric conversion module member of the present invention, the first layer is preferably a diffusion prevention layer and the second layer is a thermoelectric conversion layer. More preferably, the first layer is a diffusion prevention layer, the second layer is a thermoelectric conversion layer and the third layer is a diffusion prevention layer.

[0218] The method for producing a thermoelectric conversion module member of the present invention may include other steps before or after the first step and / or the second step.

[0219] Example

[0220] The present invention is described below by way of examples, but the present invention is not limited to these examples.

[0221] <Material (1) Preparation>

[0222] [Materials 1-1]

[0223] Raw material elements (Ge, Te, Cu, Bi) with a purity of 99.9% or more (Ge: manufactured by Furuuchi Chemical, Te and Bi: manufactured by Osaka Asahi Metal, Cu: manufactured by High Purity Chemical) are mixed at a predetermined composition ratio to form a composition formula Ge 0.95 Bi 0.05 Cu 0.03 Te, vacuum sealed in a quartz tube (2×10 -4 Pa), melted in an electric furnace (950°C x 5 hours), and then rapidly cooled with water. The obtained sample was crushed in an agate mortar to obtain a polycrystalline powder of Ge 0.95 Bi 0.05 Cu 0.03 Te is used as material 1-1.

[0224] [Materials 1-2]

[0225] MnSi produced by Toyoshima Corporation was crushed using an agate mortar. 1.73 , to obtain powdered MnSi 1.73 As material 1-2.

[0226] <Material (2) Preparation>

[0227] [Material 2-1]

[0228] Metal Ni powder (produced by Furuuchi Chemical, purity 99.9% or more, -100 mesh) was used as material 2-1. That is, material 2-1 was material (1):metal Ni=0:100 (weight basis).

[0229] [Material 2-2]

[0230] Material 2-2 was obtained by mixing metal Ni powder (1.90 g, manufactured by Furuuchi Chemical, purity 99.9% or more, -100 mesh) with material 1-1 (0.10 g). That is, material 2-2 was material (1):metal Ni=5:95 (by weight).

[0231] [Materials 2-3]

[0232] Material 2-3 was obtained by mixing metal Ni powder (1.44 g, manufactured by Furuuchi Chemical, purity 99.9% or more, -100 mesh) with material 1-1 (0.16 g). That is, material 2-3 was material (1):metal Ni=10:90 (by weight).

[0233] [Materials 2-4]

[0234] Material 2-4 was obtained by mixing metal Ni powder (1.05 g, manufactured by Furuuchi Chemical, purity 99.9% or more, -100 mesh) with material 1-1 (0.45 g). That is, material 2-4 was material (1):metal Ni=30:70 (by weight).

[0235] [Materials 2-5]

[0236] Material 2-5 was obtained by mixing metal Ni powder (1.74 g, manufactured by Furuuchi Chemical, purity 99.9% or more, -100 mesh) with material 1-1 (1.74 g). That is, material 2-5 was material (1):metal Ni=50:50 (by weight).

[0237] [Materials 2-6]

[0238] Material 2-6 was obtained by mixing metal Ni powder (0.90 g, manufactured by Furuuchi Chemical, purity 99.9% or more, -100 mesh) with material 1-2 (0.10 g). That is, material 2-6 was material (1):metal Ni=10:90 (based on weight).

[0239] <Manufacturing of thermoelectric conversion module components>

[0240] [Example 1]

[0241] A carbon punch was placed in a carbon die for spark plasma sintering, 0.3 g of material 2-3 was filled, 2.5 g of material 1-1 was filled, and 0.3 g of material 2-3 was filled, and then the die was covered with a carbon punch. The thermoelectric conversion module component was obtained by spark plasma sintering under the following conditions.

[0242] Device: DR.SINTER LABSPS-511S (manufactured by Fuji Denpa Koki Co., Ltd.)

[0243] Mold: Carbon mold inner diameter

[0244] Atmosphere: Argon 0.05MPa

[0245] External pressure: 40MPa

[0246] Heating temperature: 550℃

[0247] Retention time: 10 minutes

[0248] [Example 2]

[0249] A carbon punch was placed in a carbon die for spark plasma sintering, 0.3 g of material 2-4 was filled, 2.5 g of material 1-1 was filled, and 0.3 g of material 2-4 was filled, and then the die was capped with a carbon punch. The spark plasma sintering was performed to obtain a thermoelectric conversion module component. The spark plasma sintering was performed under the same conditions as in Example 1.

[0250] [Example 3]

[0251] A carbon punch was placed in a carbon die for spark plasma sintering, 0.3 g of material 2-6 was filled, 1.1 g of material 1-2 was filled, and 0.3 g of material 2-6 was filled, and then the die was capped with a carbon punch. The spark plasma sintering was performed to obtain a thermoelectric conversion module component. The spark plasma sintering was performed under the same conditions as in Example 1 except that the heating temperature was 800°C.

[0252] [Comparative Example 1]

[0253] A carbon punch was placed in a carbon die for spark plasma sintering, and 0.3 g of material 2-1 was filled, 2.5 g of material 1-1 was filled, and after 0.3 g of material 2-1 was filled, the die was capped with a carbon punch. The spark plasma sintering was performed to obtain a thermoelectric conversion module component. The spark plasma sintering was performed under the same conditions as in Example 1.

[0254] [Comparative Example 2]

[0255] A carbon punch was placed in a carbon die for spark plasma sintering, and 0.3 g of material 2-2 was filled, 2.5 g of material 1-1 was filled, and 0.3 g of material 2-2 was filled, and then the die was capped with a carbon punch. The spark plasma sintering was performed to obtain a thermoelectric conversion module component. The spark plasma sintering was performed under the same conditions as in Example 1.

[0256] [Comparative Example 3]

[0257] A carbon punch was placed in a carbon die for spark plasma sintering, and 0.3 g of material 2-5 was filled, 2.5 g of material (1-1) was filled, and 0.3 g of material 2-5 was filled, and then the die was covered with a carbon punch. The spark plasma sintering was performed to obtain a thermoelectric conversion module component. The spark plasma sintering was performed under the same conditions as in Example 1.

[0258] [Comparative Example 4]

[0259] A thermoelectric conversion module member was obtained in the same manner as in Example 1 except that the material 2-3 was not filled.

[0260] The thermoelectric conversion module components prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were visually observed for peeling between the thermoelectric conversion layer and the diffusion prevention layer. If no peeling was observed, the bonding was evaluated as excellent, and if peeling was observed, the bonding was evaluated as poor.

[0261] <Heat resistance evaluation>

[0262] The initial resistivity ρ(0) of each thermoelectric conversion module component produced in Examples 1 to 3 and Comparative Example 4 was measured. The resistivity measurement was carried out in the following manner. For the thermoelectric conversion module component cut into a rectangular shape, the resistance value in the height direction was measured by a two-terminal method. The rectangular shape had an anti-diffusion layer as the bottom, and the lengths of the height, width, and depth were within the range of 5 to 6 mm in height, 1 to 3 mm in width, and 1 to 3 mm in depth, respectively. Copper plates were used as terminals, and In-Ga solder was used to electrically connect the terminals to the thermoelectric conversion module component. The initial resistivity ρ(0) of the thermoelectric conversion module component was calculated from the obtained resistance value.

[0263] Next, In-Ga solder is evenly applied on the ceramic plate, and a rectangular thermoelectric conversion module component is placed on it with the diffusion prevention layer as the bottom surface, thereby making a sample. The sample is placed in an oven heated to 500°C, and the sample is taken out after 12 hours. The thermoelectric conversion module component is removed from the ceramic plate, and the resistivity (12h) of the thermoelectric conversion module component is measured in the same way as above. Here, the following evaluation can be performed: the smaller the ratio of the initial resistivity ρ(0) to the resistivity ρ(12h), the higher the heat resistance of the thermoelectric conversion module component. The results obtained are shown in Table 1.

[0264] In uses a reagent with a purity of 99.999% (model: INE13GB) manufactured by a high-purity chemical company, and Ga uses a reagent with a purity of 99.9999% (model: GAE14 PB) manufactured by a high-purity chemical company. The weight ratio of In to Ga is weighed to be 25:75, and the mixture is stirred while heating on a heating plate to obtain a uniform In-Ga solder.

[0265]

Table 1

[0266]

[0267] Industrial Applicability

[0268] The thermoelectric conversion module component of the present invention can be used as a component of a thermoelectric conversion power generation device for waste heat power generation in engines of mobile bodies such as automobiles, ships, trucks, and buses; a component of a thermoelectric conversion power generation device for waste heat power generation in manufacturing plants, power plants, and incineration sites for steel, non-ferrous metals, castings, and chemicals. In addition, the thermoelectric conversion module component of the present invention can be applied to various fields such as power generation from naturally occurring heat sources such as geothermal or solar heat, and power generation from fuel combustion heat.

Claims

1. A thermoelectric conversion module component comprising a thermoelectric conversion layer and a diffusion prevention layer in contact with the thermoelectric conversion layer, The thermoelectric conversion layer is a layer containing a thermoelectric conversion material having a silicon element or a tellurium element. The diffusion prevention layer is a layer containing a metal and a thermoelectric conversion material that is the same as the thermoelectric conversion material contained in the thermoelectric conversion layer, and the thermoelectric conversion material and the metal in the diffusion prevention layer form a sea-island phase separation structure. The amount of the thermoelectric conversion material in the diffusion prevention layer is 15 to 50 parts by weight relative to 100 parts by weight of the metal, the particle size of the metal is 200 μm or less, and the particle size of the thermoelectric conversion material is 100 μm or less.

2. The component for a thermoelectric conversion module according to claim 1, wherein the thermoelectric conversion material is at least one material selected from the group consisting of materials having, at 25 °C, a crystal structure belonging to the space group R-3m and having Bi2Te 3-x Se x (0 < x < 3) as the main phase, materials having, at 25 °C, a crystal structure belonging to the space group R-3m and having Bi 2-y Sb y Te3 (0 ≤ y ≤ 2) as the main phase, materials having, at 25 °C, a crystal structure belonging to the space group R3m and having GeTe as the main phase, materials having, at 25 °C, a crystal structure belonging to the space group R-3m and having GeBi2Te4 as the main phase, materials having, at 25 °C, a crystal structure belonging to the space group P-3m1 and having GeBi4Te7 as the main phase, materials having, at 25 °C, a crystal structure belonging to the space group Fm-3m and having SnTe as the main phase, materials having, at 25 °C, a crystal structure belonging to the space group Fm-3m and having PbTe as the main phase, materials having, at 25 °C, a crystal structure of the CaF2 type and having Mg2Si 1- z Sn z (0 ≤ z < 1) as the main phase, materials having, at 25 °C, a crystal structure belonging to the space group Cmca and having FeSi2 as the main phase, materials having, at 25 °C, a crystal structure of the chimney-ladder type and having MnSi γ (1.7 ≤ γ ≤ 1.8) as the main phase, and materials having, at 25 °C, a crystal structure of the B20 type and having CoSi as the main phase. 3 . A thermoelectric conversion module comprising a pair of electrodes and the thermoelectric conversion module component according to claim 1 or 2 provided between the pair of electrodes.

4. A method for manufacturing a thermoelectric conversion module component, which is the method for manufacturing a thermoelectric conversion module component according to claim 1 or 2, The manufacturing method comprises a first step, a second step and a sintering step. In the first step, the first layer is formed by placing one of the following material 1 and the following material 2 or a sintered body thereof in a forming mold; In the second step, the other of the material 1 and the material 2 or a sintered body thereof is arranged in the molding die so as to contact the first layer formed in the first step, thereby forming a second layer and obtaining a laminated body; In the sintering step, the thermoelectric conversion module component is obtained by sintering the laminated body obtained in the second step. Material 1: Thermoelectric conversion material containing silicon or tellurium, Material 2: A composition containing the metal and the same thermoelectric conversion material as the material 1 in a ratio of 15 to 50 parts by weight of the thermoelectric conversion material to 100 parts by weight of the metal, wherein the particle size of the metal is 200 μm or less and the particle size of the thermoelectric conversion material is 100 μm or less.

5. The manufacturing method according to claim 4 further comprises the following step in the second step: a third layer is formed by arranging the material 1 and the material 2 which is the same as the first layer or a sintered body thereof on the opposite side of the first layer in a manner that the material 1 and the material 2 are in contact with the second layer, thereby obtaining a laminate.

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