A p-type indium telluride thermoelectric material, its preparation method, and a thermoelectric power generation device.

Abstract

This invention provides a p-type indium telluride thermoelectric material, its preparation method, and a thermoelectric power generation device. The chemical formula of the p-type indium telluride thermoelectric material is InTe. 1‑x or Pb y In 1‑y Te 1‑z Among them, -0.05

Description

Technical Field

[0001] This invention relates to the field of thermoelectric materials technology, and in particular to a p-type indium telluride thermoelectric material, its preparation method, and a thermoelectric power generation device. Background Technology

[0002] Thermoelectric conversion technology is an environmentally friendly energy conversion technology that utilizes semiconductor thermoelectric materials to directly convert heat energy into electrical energy. It features long lifespan, no moving parts, no noise, high reliability, and strong environmental adaptability, making it crucial for applications in industrial waste heat recovery, low-grade environmental energy harvesting, and deep-sea and deep-space exploration. The cooling efficiency of thermoelectric materials is primarily determined by the dimensionless thermoelectric figure of merit zT = S. 2 The evaluation is based on σT / κ, where S is the Seebeck coefficient (V·K). -1 ), where σ is the conductivity (S·m) -1 ), where κ is the thermal conductivity (W·m). -1 ·K -1 (T represents Kelvin temperature (K)). Over the past 30 years, research on thermoelectric materials has focused on the mid-temperature and above regions, such as PbTe, CoSb3, semi-Heusler materials, and SiGe. Industrial waste heat, however, is mainly concentrated in the lower temperature range of 300-600K. Correspondingly, besides the traditional Bi2Te3, only a few laboratory-grade thermoelectric materials exist, such as p-GeTe, p-MgAgSb, SnSe, and n-Mg3Sb2. Therefore, actively exploring inexpensive, stable, and high-performance near-room-temperature thermoelectric materials is becoming increasingly urgent.

[0003] High-performance thermoelectric materials require high Seebeck coefficient, high electrical conductivity, and low thermal conductivity. Novel InTe materials along the

[110] direction can simultaneously achieve high electrical performance and low thermal performance.

[110] / κ

[001] =~0.5@300K, σ

[110] / σ

[001] =~3.1@300K, which conforms to the design concept of "electron crystal-phonon glass" for thermoelectric materials and is a potential thermoelectric power generation material. It is worth noting that although InTe has the characteristic of uniform melting, and can obtain large-size single crystals by the drop method or the Czochralski method to utilize its high thermoelectric properties in the

[110] direction, its quasi-one-dimensional chain crystal structure makes single crystals very easy to cleave along the (110) plane, which brings great difficulties to further processing and testing. Although polycrystalline samples have strong mechanical properties, due to the introduction of grain boundary scattering, their electrical conductivity shows a trend of first increasing and then decreasing with increasing temperature, which leads to extreme deterioration of electrical conductivity below the intermediate temperature.

[0004] There is a need to develop a material preparation process that can simultaneously achieve high thermoelectric performance with single crystal orientation and strong mechanical properties with polycrystals to promote the power generation application of indium telluride thermoelectric materials. Summary of the Invention

[0005] To solve the above problems, the present invention provides a p-type indium telluride thermoelectric material, its preparation method, and a thermoelectric power generation device to meet the preparation requirements of high-efficiency thermoelectric power generation devices and maximize the power generation efficiency of the devices.

[0006] In the first aspect of the present invention, a p-type indium telluride thermoelectric material is provided. The chemical formula of the p-type indium telluride thermoelectric material is InTe 1-x or Pb y In 1-y Te 1-z , where -0.05 < x < 0.05, y < 0.05, -0.05 < z < 0.05. Preferably, -0.01 < x < 0.01, y < 0.02, -0.01 < z < 0.01. In some specific embodiments, the chemical formula of the p-type indium telluride thermoelectric material is InTe 0.999 , Pb 0.001 In 0.999 Te.

[0007] In the second aspect of the present invention, a preparation method of a p-type indium telluride thermoelectric material is provided. The preparation method includes the following steps: according to the stoichiometric ratio of the p-type indium telluride thermoelectric material, subjecting each component material to high-temperature melting to obtain the melted material; subjecting the melted material to single crystal growth to obtain a single crystal; subjecting the single crystal growth to single crystal

[110] direction orientation and performing plastic deformation along the single crystal

[110] direction to obtain the p-type indium telluride thermoelectric material.

[0008] Furthermore, the method of single crystal growth is the Bridgman method or the zone melting method; where, when the method of single crystal growth is the Bridgman method, the growth temperature gradient is 5 °C / cm to 40 °C / cm, the growth rate is 0.2 mm / h to 5 mm / h, and the rotation speed is 0 r / min to 20 r / min; when the method of single crystal growth is the zone melting method, the growth temperature zone is 1 cm to 5 cm, the growth rate is 0.2 mm / h to 5 mm / h, and the rotation speed is 0 r / min - 20 r / min. It should be noted that the single crystal growth includes crystal selection and isodiametric processes. Preferably, the crucible for single crystal growth is one of a conical head carbon-coated quartz crucible, a graphite crucible, or a boron nitride crucible; the conical angle of the crucible for single crystal growth is 70° to 30°. The single crystal

[110] direction is determined by a single crystal orientation instrument; the single crystal

[110] direction is obtained by cutting to obtain a single crystal hot pressing deformation sample.

[0009] A third aspect of this invention provides another method for preparing a p-type indium telluride thermoelectric material. This method includes the following steps: melting the component materials at high temperature according to the stoichiometric ratio of the p-type indium telluride thermoelectric material to obtain the molten material; crushing and sieving the molten material to obtain polycrystalline powder; and plastically deforming the polycrystalline powder to obtain the p-type indium telluride thermoelectric material. The obtained p-type indium telluride thermoelectric material is a highly oriented polycrystalline material.

[0010] Furthermore, the average particle size of the crushed and sieved polycrystalline powder is greater than 100 μm.

[0011] Furthermore, all the component materials are high-purity raw materials with a purity greater than 99.9%; the high-temperature melting is carried out in a vacuum environment; the parameters of the high-temperature melting are: temperature of 750℃~1000℃, time of 0.5h~10h, heating rate of less than or equal to 50℃ / min, and cooling rate is unlimited.

[0012] Furthermore, the plastic deformation is a single hot-press sintering at a temperature of 450℃ to 620℃ and a pressure of 30MPa to 80MPa. Preferably, when hot-pressing a single-crystal sample, the sintering temperature is 600℃ and the pressure is 40MPa to 50MPa. Hot-pressing sintering can flatten and compact the oriented single-crystal sample, maintaining its orientation while refining the grains and improving mechanical strength. More preferably, the hot-pressing sintering is achieved using different hot-pressing molds. When using a conventional cylindrical hot-pressing mold, the mold diameter is preferably larger than the maximum dimension perpendicular to the single crystal

[110] . When hot-pressing a polycrystalline sample, preferably, the sintering temperature is 500℃ to 550℃ and the pressure is 40MPa to 50MPa. More preferably, the diameter of the hot-pressing mold for polycrystalline sample sintering is 10mm to 25mm. Based on the technical solution disclosed in this invention, those skilled in the art are motivated to optimize the process by selecting the values ​​of x, y, and z, adjusting the melting temperature, single crystal growth method and process, hot pressing temperature and pressure, etc., according to the actual production needs.

[0013] A fourth aspect of the present invention provides a method for fabricating a p-type indium telluride-based thermoelectric power generation device, comprising the following steps: determining the size of a thermoelectric arm based on the differences in thermal and electrical transport properties between the p-type indium telluride thermoelectric material and the paired n-type thermoelectric material; preparing a cutting and plating interface between the p-type indium telluride thermoelectric material and the n-type thermoelectric material according to the size to obtain the thermoelectric arm; and integrating the thermoelectric arm with a ceramic substrate by high-temperature welding to obtain the p-type indium telluride-based thermoelectric power generation device.

[0014] Furthermore, the n-type thermoelectric material is bismuth telluride; preferably, the n-type thermoelectric material is commercially available bismuth telluride. The thermoelectric arm was optimized using COMSOL commercial software, resulting in a height greater than 5mm. The total internal resistance formula (1) is shown below. It can be seen that as A... p / A n The change in total internal resistance first decreases and then increases;

[0015]

[0016] Among them, A p Let A be the cross-sectional area of ​​p-type indium telluride. n Let H be the cross-sectional area of ​​n-type bismuth telluride, H be the height of the thermoelectric arm, and r be the cross-sectional area of ​​the bismuth telluride. p r is the conductivity of p-type indium telluride. n The conductivity of n-type bismuth telluride;

[0017] The formula for calculating the total thermal conductivity of thermoelectric particles (2) is shown below. It can be seen that the larger the cross-sectional area of ​​the material with low thermal conductivity, the better, as it can reduce the total thermal conductivity of the system.

[0018]

[0019] Among them, A p Let A be the cross-sectional area of ​​p-type indium telluride. n Here, H is the cross-sectional area of ​​n-type bismuth telluride, H is the height of the thermoelectric arm, and k is the cross-sectional area of ​​the bismuth telluride. p The thermal conductivity of p-type indium telluride is k. n The thermal conductivity of n-type bismuth telluride is given. Combining formulas (1) and (2), the cross-sectional area ratio between p-type indium telluride and n-type bismuth telluride is greater than 2. Preferably, in the example, the cross-sectional areas of p-type indium telluride and n-type bismuth telluride are close to 3. More preferably, the p-type indium telluride and n-type bismuth telluride are cut, thinned, cleaned, electroplated, chemically plated, magnetron sputtered, or vapor-deposited according to the substrate size. The ceramic substrate is a high thermal conductivity ceramic substrate such as aluminum nitride or alumina. The cleaning process removes surface impurities, including but not limited to acid cleaning with sulfuric acid, nitric acid, hydrofluoric acid, etc., alkaline cleaning with potassium hydroxide, sodium hydroxide, etc., and oil stain cleaning with acetone, alcohol, etc., to achieve a high bonding effect. Preferably, the coating interface is a low diffusion, high temperature resistant, and high electrical conductivity metal material, including but not limited to nickel, titanium, tungsten, molybdenum, etc., and in some specific embodiments, the coating interface is a 1-20 micrometer thick nickel metal. The thermoelectric arm is integrated with the ceramic substrate via pn high-temperature series welding. The p-type indium telluride and n-type bismuth telluride are vacuum-welded under high temperature and pressure using different high-temperature solders according to the operating temperature, with a welding pressure of less than 100 kPa.

[0020] The fifth aspect of the present invention provides a p-type indium telluride-based thermoelectric power generation device, which is prepared according to the above-described method for preparing a p-type indium telluride-based thermoelectric power generation device.

[0021] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0022] This invention provides a p-type indium telluride thermoelectric material, its preparation method, and a thermoelectric power generation device. Employing single-crystal deformation and grain sieving hot-pressing processes, this invention provides a high-strength and high-efficiency p-type indium telluride thermoelectric material with an optimal performance temperature range near room temperature, which is beneficial for developing low-temperature thermoelectric cooling devices. Furthermore, using simulation design technology, a fabrication scheme for a high-efficiency indium telluride-based thermoelectric power generation device is provided, and utilizing high-temperature welding technology, a fabrication method for a high-efficiency indium telluride-based thermoelectric power generation device is provided.

[0023] In this invention, by growing single crystals, the unique thermoelectric transport anisotropy of InTe can be utilized to simultaneously obtain high electrical conductivity and low thermal conductivity. However, single crystals have poor mechanical properties and are prone to cleavage, which is not conducive to material processing and device fabrication. By using directional single crystal hot pressing and reshaping, the mechanical properties of the strongly anisotropic InTe can be improved through grain refinement, making it suitable for the fabrication of thermoelectric power generation devices. On the other hand, polycrystalline InTe has strong mechanical properties, but the orientation degree of the (110) crystal plane is poor, which makes it impossible to maximize thermoelectric performance. Moreover, for small-grained InTe, there is strong grain boundary scattering, which reduces near-room temperature thermoelectric performance. By using the grain sieving hot pressing process, the unfavorable grain boundary scattering can be eliminated by utilizing the large grain size. It can also effectively improve the texture of polycrystalline InTe, which is beneficial to the improvement of thermoelectric performance. In addition, based on the mismatch of electrothermal transport between p-type and n-type thermoelectric arms of equal size, an efficient power generation device fabrication scheme is designed through size and interface simulation. It is predicted that the power generation efficiency is >7% at a temperature difference of 290 degrees Celsius. Attached Figure Description

[0024] Figure 1 This is a single crystal diagram of InTe in Embodiment 1 of the present invention;

[0025] Figure 2 This is an X-ray powder diffraction pattern of InTe single crystal after deformation in Example 1 of the present invention;

[0026] Figure 3 This is a graph showing the conductivity test results of the p-type indium telluride thermoelectric material in Embodiment 2 of the present invention;

[0027] Figure 4 The graph shows the Seebeck coefficient test results of the p-type indium telluride thermoelectric material in Embodiment 2 of the present invention.

[0028] Figure 5This is a graph showing the thermal conductivity test results of the p-type indium telluride thermoelectric material in Embodiment 2 of the present invention;

[0029] Figure 6 The graph shows the thermoelectric figure of merit zT performance test results of the p-type indium telluride thermoelectric material in Embodiment 2 of the present invention;

[0030] Figure 7 This is a graph showing the efficiency test of the thermoelectric device in Embodiment 3 of the present invention;

[0031] Figure 8 This is a diagram showing the predicted power generation efficiency after device interface optimization in Embodiment 3 of the present invention. Detailed Implementation

[0032] As the background technology indicates, InTe is a novel near-room temperature thermoelectric material, but there is still a lack of fabrication processes and power generation device preparation schemes that can simultaneously achieve both thermoelectric and mechanical properties. This invention addresses the problems of weak mechanical properties in p-type single-crystal InTe and poor near-room temperature temperature thermoelectric properties in p-type polycrystalline InTe. Through single-crystal growth and grain refinement strengthening, both mechanical and thermoelectric properties are improved simultaneously. This invention provides a high-strength and high-efficiency p-type InTe thermoelectric material and its preparation method, meeting the requirements for the fabrication of high-efficiency thermoelectric power generation devices. Furthermore, this invention provides a simulation design scheme and integration technology for InTe-based thermoelectric power generation devices to maximize device power generation efficiency.

[0033] The first aspect of this invention provides a p-type indium telluride thermoelectric material, wherein the chemical formula of the p-type indium telluride thermoelectric material is InTe. 1-x or Pb y In 1-y Te 1-z Among them, -0.05 <x<0.05,y<0.05,-0.05<z<0.05。

[0034] The second aspect of the present invention provides a method for preparing a p-type indium telluride thermoelectric material, the method comprising the following steps: according to the stoichiometric ratio of the p-type indium telluride thermoelectric material, the components are smelted at high temperature to obtain the smelted material; the smelted material is subjected to single crystal growth to obtain a single crystal; the single crystal is oriented in the single crystal

[110] direction and plastically deformed along the single crystal

[110] direction to obtain the p-type single crystal indium telluride thermoelectric material.

[0035] The third aspect of the present invention provides another method for preparing p-type indium telluride thermoelectric material, the method comprising the following steps: according to the stoichiometric ratio of p-type indium telluride thermoelectric material, the components are smelted at high temperature to obtain smelted material; the smelted material is crushed and sieved to obtain polycrystalline powder; the polycrystalline powder is plastically deformed to obtain p-type indium telluride thermoelectric material.

[0036] A fourth aspect of the present invention provides a method for fabricating a p-type indium telluride-based thermoelectric power generation device, comprising the following steps: determining the size of a thermoelectric arm based on the differences in thermal and electrical transport properties between the p-type single-crystal indium telluride thermoelectric material and the paired n-type thermoelectric material; preparing a cutting and plating interface between the p-type indium telluride thermoelectric material and the n-type thermoelectric material according to the size to obtain the thermoelectric arm; and integrating the thermoelectric arm with a ceramic substrate by high-temperature welding to obtain the p-type indium telluride-based thermoelectric power generation device.

[0037] The fifth aspect of the present invention provides a p-type indium telluride-based thermoelectric power generation device, which is prepared according to the above-described method for preparing a p-type indium telluride-based thermoelectric power generation device.

[0038] To provide a more specific and clear understanding of the objectives, technical solutions, and effects of this invention, the following provides a detailed description of the invention. It should be understood that the following embodiments are only a part of the embodiments of this invention, and not all of them. Therefore, the embodiments of this invention provided below are only for the purpose of this invention and are not intended to limit the invention.

[0039] In the following embodiments, the electrical performance testing equipment was a Japanese ZEM-3, and the thermal diffusivity D was tested using a German Netzsch laser thermal conductivity meter LFA-450; thermal conductivity was determined by k = C. p Dρ is calculated, density ρ is obtained by Archimedes' method, and specific heat C is obtained by calculation. p It was calculated using the Dulong-Petty formula.

[0040] Example 1

[0041] According to the chemical formula InTe 0.999 or Pb y In 1-y Te (where y = 0, 0.0001, 0.0005, and 0.001), is used to weigh high-purity elemental In and Te; the weighed material is placed in a carbon-plated quartz tube, and a vacuum is drawn to 10. -4 Pa was used to seal the tube; the sealed quartz tube was placed in a high-temperature sintering furnace, heated to the target temperature of 850℃ for 5 hours, held at that temperature for 10 hours, and finally cooled to 373K for 10 hours before the power was turned off and the tube cooled to room temperature with the furnace. The resulting stoichiometric ratio was InTe. 0.999 or Pb y In 1-y A pure phase sample of Te (where y = 0, 0.0001, 0.0005 and 0.001).

[0042] Example 2

[0043] Based on the stoichiometry obtained from Implementation Case 1, InTe 0.999The ingot is placed into a carbon-plated conical quartz tube with a diameter of 20 mm and a cone angle of 30°, and a vacuum is drawn to 10°. -4 Pa is used to seal the tube; the conical part of the sealed quartz tube is placed downwards in a dual-temperature zone single crystal lowering furnace, with the conical part located between the two temperature zones; after 5 hours, both temperature zones are simultaneously heated to the target temperature of 750℃ and held for 10 hours, then after 24 hours, the upper high-temperature zone is cooled to 710℃ and the lower low-temperature zone is cooled to 670℃, and held for a long time; the conical quartz tube is rotated at 5 rpm and lowered at a speed of 5 mm / h. When the ingot has completely entered the low-temperature zone, the crystal growth ends. Finally, after 24 hours, the temperature is lowered to 373K and the power is turned off to cool to room temperature with the furnace. The obtained single crystal is as follows: Figure 1 As shown, from Figure 1 As can be seen, this method can obtain large-size complete single crystals.

[0044] The obtained single crystal was oriented to obtain the single crystal

[110] direction. A sample with a width of 15 mm was obtained by cutting and placed in a graphite mold with a diameter of 20 mm. The vacuum was evacuated to below 10 Pa, and the temperature was heated to 610 °C at a heating rate of 50 °C / min. Then, the pressure was increased to 50 MPa for hot pressing sintering. The sintering time was 20 min. After sintering, the temperature was lowered to room temperature for 15 min. The X-ray powder diffraction pattern of the deformed InTe single crystal is shown below. Figure 2 As shown. From Figure 2 It can be seen that the high orientation degree of the (110) crystal plane can be effectively maintained through single-crystal directional reheat deformation. It should be understood that in the vector representation of crystals, [] represents the crystal direction index, and () represents the crystal plane index.

[110] is the crystal direction index, which in this patent is equivalent to the direction of the vector 1*x+1*y+0*z and the direction of the straight line that satisfies x=y. The single crystal

[110] direction and the (110) crystal plane are perpendicular to each other.

[0045] For the Pb y In 1-y Te (y = 0, 0.0001, 0.0005 and 0.0001) ingots were crushed and sieved through a 50-mesh sieve. The resulting large grains were placed in a graphite mold with a diameter of 10 mm, and the mold was evacuated to below 10 Pa. The mold was heated to 550 °C at a heating rate of 50 °C / min, and then pressurized to 50 MPa for hot pressing sintering. The sintering time was 20 min, and after sintering, the mold was cooled to room temperature for 15 min.

[0046] Figure 3 This is a graph showing the conductivity test results of Embodiment 2 of the present invention. Figure 3 As can be seen from this, the high texture of single-crystal deformation can take advantage of the high electrical conductivity in the

[110] direction.

[0047] Figure 4This is a graph showing the Seebeck coefficient test results of Embodiment 2 of the present invention. Figure 4 As can be seen from this, the high texture of single crystal deformation can utilize the high electrical conductivity in the

[110] direction without adversely affecting the Seebeck coefficient.

[0048] Figure 5 This is a graph showing the thermal conductivity test results of Embodiment 2 of the present invention. Figure 5 As can be seen from the data, the high texture of single-crystal deformation can take advantage of the low thermal conductivity in the

[110] direction.

[0049] Figure 6 This is a graph showing the thermoelectric figure of merit calculation results of Embodiment 2 of the present invention. Figure 6 As can be seen, single-crystal deformation can greatly improve the thermoelectric properties of materials, and sieved grains can effectively improve near-room temperature thermoelectric properties.

[0050] Example 3

[0051] The obtained single-crystal deformed p-type indium telluride and commercial n-type bismuth telluride were cut to obtain a thermoelectric sheet with high orientation in the indium telluride

[110] direction and in-plane orientation in the bismuth telluride, with a thickness of 6.8 mm. Using a commercially common electroplating method, the anode was made of metallic nickel and the cathode was the thermoelectric material. The sample and the anode were placed in an electrolyte and then a direct current was applied to deposit a 10-micron nickel plating layer on the cathode sample. The electroplated thermoelectric sheet was cut according to the size optimized by simulation to obtain a thermoelectric arm with a cross-sectional area of ​​InTe: 3 mm × 3 mm × 6.8 mm and bismuth telluride: 1.7 mm × 1.7 mm × 6.8 mm. The alumina ceramic substrate and the thermoelectric arm were connected in series using silver paste or copper-tin solder paste. The welding conditions were vacuum, pressure 5 kPa, welding time 30 minutes, and the final device interface resistance was 650 mΩ. The power generation efficiency was 4.8% at a temperature difference of 290 °C. Theoretical predictions suggest that if the interface resistance is reduced to the conventional 10mΩ, the power generation efficiency will be 7% at a temperature difference of 290℃.

[0052] Figure 7 This is a graph showing the test results of the thermoelectric device in Embodiment 3 of the present invention. Figure 8 The graph shows the predicted power generation efficiency of the device after interface resistance optimization. Figure 7 and Figure 8 As can be seen, indium telluride-based thermoelectric devices hold promise for achieving high power generation efficiency near room temperature.

[0053] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for fabricating a p-type indium telluride-based thermoelectric power generation device, characterized in that, Includes the following steps: The dimensions of the thermoelectric arm are determined based on the differences in thermal and electrical transport properties between p-type indium telluride thermoelectric materials and paired n-type thermoelectric materials; According to the stated dimensions, the p-type indium telluride thermoelectric material and the n-type thermoelectric material are cut and the coating interface is prepared to obtain the thermoelectric arm; The thermoelectric arm is integrated with a ceramic substrate by high-temperature welding to obtain a p-type indium telluride-based thermoelectric power generation device. The chemical formula of the p-type indium telluride thermoelectric material is InTe. 1-x or Pb y In 1-y Te 1-z Among them, -0.05 <x<0.05,y<0.05,-0.05<z<0.05; The preparation method of the p-type indium telluride thermoelectric material includes the following steps: Based on the stoichiometry of p-type indium telluride thermoelectric material, the components are smelted at high temperature to obtain the smelted material. The smelted material is subjected to single-crystal growth to obtain a single crystal; The single crystal growth is oriented in the single crystal [110] direction, and plastic deformation is performed along the single crystal [110] direction to obtain the p-type indium telluride thermoelectric material.

2. The method for fabricating a p-type indium telluride-based thermoelectric power generation device according to claim 1, characterized in that, The single crystal growth method is either the descending method or the zone melting method; In the case where the single crystal growth method is the descending method, the growth temperature gradient is 5℃ / cm to 40℃ / cm, and the growth rate is 0.2 mm / h to 5 mm / h. When the single crystal growth method is zone melting, the growth temperature range is 1 cm to 5 cm, and the growth rate is 0.2 mm / h to 5 mm / h.

3. The method for fabricating a p-type indium telluride-based thermoelectric power generation device according to claim 1, characterized in that, The preparation method includes the following steps: Based on the stoichiometry of p-type indium telluride thermoelectric material, the components are smelted at high temperature to obtain the smelted material. The smelted material is crushed and sieved to obtain polycrystalline powder; The polycrystalline powder is plastically deformed to obtain the p-type indium telluride thermoelectric material.

4. The method for fabricating a p-type indium telluride-based thermoelectric power generation device according to claim 3, characterized in that, The average particle size of the polycrystalline powder after crushing and sieving is greater than 100 μm.

5. The method for fabricating a p-type indium telluride-based thermoelectric power generation device according to claim 2 or 3, characterized in that, All components are high-purity raw materials with a purity greater than 99.9%; The high-temperature melting is carried out in a vacuum environment; the parameters of the high-temperature melting are: temperature of 750℃~1000℃, time of 0.5 h~10 h, heating rate of less than or equal to 50℃ / min, and cooling rate of unlimited.

6. The method for preparing a p-type indium telluride-based thermoelectric power generation device according to claim 2 or 3, characterized in that, The plastic deformation is a single hot pressing sintering process, with a temperature of 450℃~620℃ and a pressure of 30 MPa~80 MPa.

7. The method for fabricating a p-type indium telluride-based thermoelectric power generation device according to claim 1, characterized in that, The n-type thermoelectric material is bismuth telluride; The thermoelectric arm was optimized using COMSOL commercial software, resulting in a height greater than 5 mm. The formula for total internal resistance (1) is shown below. （1） Among them, A p Let A be the cross-sectional area of ​​p-type indium telluride. n Let H be the cross-sectional area of ​​n-type bismuth telluride, H be the height of the thermoelectric arm, and r be the cross-sectional area of ​​the bismuth telluride. p r is the conductivity of p-type indium telluride. n The conductivity of n-type bismuth telluride; The formula (2) for calculating the total thermal conductivity of thermoelectric particles is shown below. （2） Among them, A p Let A be the cross-sectional area of ​​p-type indium telluride. n Let H be the cross-sectional area of ​​n-type bismuth telluride, and H be the height of the thermoelectric arm. k p The thermal conductivity of p-type indium telluride is... k n The thermal conductivity of n-type bismuth telluride; Combining formulas (1) and (2), the cross-sectional area ratio between p-type indium telluride and n-type bismuth telluride is greater than 2.

8. A p-type indium telluride-based thermoelectric power generation device, characterized in that, The device is prepared by the method for preparing a p-type indium telluride-based thermoelectric power generation device according to claim 1.

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