KR20190136654A - METHOD FOR MANUFACTURING Bi-Sb-Te BASED THERMOELECTRIC MATERIAL CONTAINING CARBON NANOTUBE AND THERMOELECTRIC MATERIAL MANUFACTURED THEREBY - Google Patents

Abstract

The present invention relates to a method for manufacturing a Bi-Sb-Te-based thermoelectric material containing carbon nanotubes, and a thermoelectric material manufactured thereby. The method comprises: a step (a) of combining (i) Bi-Sb-Te-based thermoelectric powder and (ii) carbon nanotubes (CNT) or CNT having a metal coating layer by means of high energy milling; and a step (b) of manufacturing a sintered body from combined powder obtained from the step (a). According to the present invention, a powder metallurgy process is applied to manufacturing of a thermoelectric material to enable mass production. In particular, CNT including a metal coating layer is combined with the Bi-Sb-Te-based thermoelectric material through mechanical alloying to increase electrical conductivity but inhibit an increase in thermal conductivity, thereby enabling a user to manufacture a thermoelectric material having enhanced mechanical properties as well as excellent figure of merit (ZT) compared to a conventional thermoelectric material.

Description

Method for manufacturing carbon nanotube-containing Bi-Sb-Te-based thermoelectric material {METHOD FOR MANUFACTURING Bi-Sb-Te BASED THERMOELECTRIC MATERIAL CONTAINING CARBON NANOTUBE AND THERMOELECTRIC MATERIAL MANUFACTURED THEREBY}

The present invention relates to a method of manufacturing a thermoelectric material and a thermoelectric material manufactured thereby, and more particularly, to a method of manufacturing a Bi-Sb-Te-based thermoelectric material containing carbon nanotubes and to a thermoelectric material manufactured thereby. will be.

A thermoelectric material is a new alternative energy material that converts thermal energy due to temperature gradient into electrical energy, and inversely, direct current is applied to one end of the material, where endothermic heat is generated and heat is converted to thermal energy.

The above-mentioned energy conversion phenomenon is called thermoelectric phenomenon, and the Seebeck effect of converting thermal energy into electrical energy is used for thermoelectric generation, and the Peltier effect of converting electrical energy into thermal energy is thermoelectric refrigeration. It is used for.

The thermoelectric power generation has the advantage that there is little noise and can easily convert heat and electricity mutually, unlike a conventional power generation device. In addition, the thermoelectric cooling is environmentally friendly because it does not use a refrigerant as in the conventional apparatus, and since there is no mechanical driving unit, there is no noise and vibration and selective cooling of the local part is possible. Therefore, its use is gradually being extended to the home appliance industry, such as high power laser diodes, measuring equipment, medical equipment, and small refrigerators.

In order for the thermoelectric material to be widely used, the thermal / electric conversion efficiency of the material must be high. Generally, the conversion efficiency of the thermoelectric material is evaluated as a figure of merit (ZT).

로 나타내며, 높은 변환효율을 나타내기 위해서는 높은 Seebeck 계수(α)와 낮은 전기비저항(ρ) 및 낮은 열전도도(κ)가 동시에 요구된다. 이들 물성들은 재료내부의 전하(carrier)와 격자진동(phonon)의 거동에 의존하는 물질상수로서, 서로 종속적인 관계를 가지고 있다. 이러한 물성들의 상호의존적인 관계는 열전재료의 연구가 진행된 이래 성능지수를 높이는데 큰 장애요소로 작용하여 왔으며, 이를 극복하기 위한 여러 연구가 활발히 진행되고 있다.The performance index of thermoelectric materials

In order to show high conversion efficiency, high Seebeck coefficient (α), low electrical resistivity (ρ), and low thermal conductivity (κ) are simultaneously required. These properties are material constants that depend on the behavior of carriers and lattice vibrations within the material and have a mutually dependent relationship. The interdependent relationship of these properties has been a major obstacle to improving the performance index since the study of thermoelectric materials, and various studies to overcome them have been actively conducted.

The performance index is divided into alloys having excellent performance indexes according to the operating temperature.Bi-Te-based in the room temperature range (below 200 ℃) and TAGS (tellurium-antimony-germanium-silver) in the mid-temperature zone (200 ~ 400 ℃) Si-Ge-based materials are used in the high-temperature regions 500-1000.

Bi-Te-based thermoelectric material, which has a high performance index at room temperature, is typically Bi ₂ Te _{3 and} is manufactured in p-type or n-type by adding Sb or Se. Currently, commercially available Bi ₂ Te _3- based materials are dissolved / It is generally manufactured by unidirectional solidification, which is a single crystal growth method based on the solidification process technology.

However, in the case of the manufacturing method using the one-way coagulation method, the manufacturing process takes a long time, there is a disadvantage that the segregation in the material occurs during the process time is uneven physical properties. In addition, Bi ₂ Te ₃ based materials have a very weak mechanical properties due to the presence of van der Waals bonds on the wall interface.

, α:제벡계수, σ: 전기전도도, k:열전도도)가 상호의존적이기 때문에 열전 성능을 향상시키기에는 한계가 있다.In addition, in the case of existing materials such as the Bi ₂ Te ₃ system, three factors that determine thermoelectric performance (thermoelectric performance ZT =

, α: Seebeck coefficient, σ: electrical conductivity, and k: thermal conductivity) are interdependent and thus there is a limit to improving thermoelectric performance.

Korea Patent Registration No. 10-1114252 (Registration Date: 2012. 02. 02.) Korea Patent Registration No. 10-1104677 (Registration Date: 2012. 01. 04.) Japanese Patent Laid-Open No. 2004-342893 (published: 2004. 12. 02.)

Technical problem to be solved by the present invention, based on the powder metallurgy process technology can not only mass-produce thermoelectric materials compared to the conventional one-way solidification method, etc., thermoelectric materials having improved mechanical properties and excellent thermoelectric performance index (ZT) It is to provide a thermoelectric material manufacturing method and a thermoelectric material produced thereby.

In order to achieve the above technical problem, the present invention provides a high energy milling of (a) (i) Bi-Sb-Te-based thermoelectric powder and (ii) carbon nanotubes (carbon nanotue, CNT) or carbon nanotubes having a metal coating layer It proposes a method for producing a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material comprising the step of complexing through and (b) producing a sintered body from the composite powder obtained in the step (b).

In addition, the Bi-Sb-Te-based thermoelectric powder in step (a) proposes a method of manufacturing a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material, characterized in that the Bi _0.5 Sb _1.5 Te ₂ .

In addition, in the step (a), the metal coating layer proposes a method for producing a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material, characterized in that made of copper (Cu), silver (Ag) or aluminum (Al). .

In addition, the composite powder obtained in the step (a) proposes a method for producing a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material, characterized in that containing 0.1 to 5.0% by weight of carbon nanotubes.

In addition, in the step (a), carbon nanotube-containing Bi-, characterized in that high energy milling is performed using planetary ball milling, attrition milling, or shaker milling. We propose a method of manufacturing Sb-Te-based thermoelectric materials.

In addition, in the step (b), the carbon nanotubes are manufactured by hot pressing (Hot Pressing, HP), discharge plasma sintering (Spark Plasma Sintering, SPS) or hot hydrostatic pressing (Hot Isostatic Pressing, HIP). A method for producing a Bi-Sb-Te-based thermoelectric material is proposed.

In addition, the step (b) proposes a method for producing a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material characterized in that the sintering is carried out at a temperature of 350 ~ 500 ℃ and a pressure of 30 ~ 80 MPa.

In another aspect of the present invention, the present invention proposes a thermoelectric material manufactured by the above method.

According to the method of manufacturing a thermoelectric material according to the present invention, mass production is possible by applying a powder metallurgy process technology for producing a thermoelectric material, and in particular, a carbon nanotube (CNT) including a metal coating layer through mechanical alloying is formed of Bi-Sb- By complexing with Te-based thermoelectric materials, the electrical conductivity is increased while the thermal conductivity is suppressed, and thus thermoelectric materials having excellent ZT and improved mechanical properties can be manufactured.

1 is a schematic diagram showing a thermoelectric material manufacturing process according to the present invention for producing a thermoelectric material by adding CNT in the Bi-Sb-Te-based thermoelectric material.
Figure 2 is a scanning electron microscope (SEM) photograph showing the shape of the BiSbTe thermoelectric powder (left) and CNT-combined BiSbTe thermoelectric composite powder (right), respectively, prepared in Examples of the present application.
3 (a) and 3 (b) are the Seebeck coefficient and electrical conductivity measurement results of the thermoelectric material sintered bodies (BST, BST + CNT and BST + Cu-CNT) prepared in Examples of the present application, respectively.
4 (a) to 4 (c) show lattice thermal conductivity, electron thermal conductivity, and thermal conductivity measurement results of the thermoelectric material sintered bodies (BST, BST + CNT, and BST + Cu-CNT) prepared in Examples of the present application, respectively.
Figure 5 is a graph comparing the thermoelectric performance index (ZT) of the thermoelectric material sintered body (BST, BST + CNT and BST + Cu-CNT) prepared in the present example.

In describing the present invention, when it is determined that detailed descriptions of related known functions or configurations may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

Embodiments in accordance with the concepts of the present invention may be variously modified and may have various forms, and specific embodiments will be illustrated in the drawings and described in detail in the present specification or application. However, this is not intended to limit the embodiments in accordance with the concept of the present invention to a particular disclosed form, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. As used herein, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof that is described, and that one or more other features or numbers are present. It should be understood that it does not exclude in advance the possibility of the presence or addition of steps, actions, components, parts or combinations thereof.

Hereinafter, the present invention will be described in detail.

1 is a schematic diagram showing an example of a process for producing a thermoelectric material by adding CNT in the Bi-Sb-Te-based thermoelectric material according to the present invention, the present invention is (a) (i) Bi-Sb-Te-based thermoelectric powder And (ii) complexing carbon nanotubes having carbon nanotubes (CNTs) or metal coating layers through high energy milling, and (b) preparing a sintered body from the composite powder obtained in step (b). It is included.

According to the present invention, it is possible to effectively control the scattering index due to the addition of CNT, through which it is possible to significantly lower the thermal conductivity. In addition, the electrical conductivity may also be improved by controlling the carrier concentration through the metal material coated on the CNT. Therefore, by controlling each factor affecting the thermoelectric performance, it is possible to improve the thermoelectric performance of the resulting thermoelectric material.

In step (a), Bi-Sb-Te is formed by mechanical alloying through high-energy milling such as planetary ball milling, attrition milling, or shaker milling. A composite powder is prepared in which a thermoelectric powder and a carbon nanotube (or a carbon nanotube having a metal coating layer on its surface) are combined.

In this case, the Bi-Sb-Te-based thermoelectric powder may further include at least one of Pb, Cu, and Se in addition to Bi, Sb, and Te, which is a main element, but is not limited thereto. It may be a powder selected from all composition ranges corresponding to the material, and may be preferably made of Bi _0.5 Sb _1.5 Te ₂ .

For reference, the Bi-Sb-Te-based thermoelectric powder may be manufactured by a milling method, a rapid solidification method, etc., and in the case of the milling method, a casting material including bismuth (Bi), antimony (Sb), and tellurium (Te) May be prepared by milling or milling each element of bismuth (Bi), antimony (Sb) and tellurium (Te). In addition, the rapid solidification method may be gas atomizing (Gas Atomizing), such as bismuth (Bi), antimony (Sb) and tellurium (Te) in a carbon crucible, and then in a high-frequency in argon (Ar) gas atmosphere By melting through induction heating and injecting the molten metal through an orifice, argon (Ar) gas may be used to produce an alloy for manufacturing thermoelectric materials including bismuth (Bi), antimony (Sb), and tellurium (Te).

The carbon nanotubes (or carbon nanotubes having a metal coating layer on the surface) are preferably added so that the composite powder obtained in the step (a) includes 0.1 to 5.0 wt% of carbon nanotubes, and the CNT is used as the content. By including the scattering index of the thermoelectric material can be effectively controlled, through which the thermal conductivity can be significantly lowered.

On the other hand, the metal coating layer of the carbon nanotube having the metal coating layer is preferably made of copper (Cu), silver (Ag) or aluminum (Al), the carbon nanotube having the metal coating layer is a carbon nanotube and a metal powder It can be prepared by mechanical mixing through milling using a ball mill, planetary mill, attrition mill, or the like, or by using carbon nanotubes and metal precursors. . Among them, as a specific example of the method using the carbon nanotubes and the metal precursor, after preparing a mixed solution of carbon nanotubes and the metal precursor, a method of forming a carbon nanotube-metal composite through drying, calcining and reduction process Alternatively, a method of preparing a mixed solution of carbon nanotubes and a metal precursor, followed by an oxidation process using an oxidizing agent, and then forming a carbon nanotube-metal composite through a reduction process may be used.

Next, in the step (b) to prepare a sintered body using the Bi-Sb-Te-based alloy-CNT (or CNT including a metal coating layer) composite powder obtained in the previous step.

It is preferable that the sintered body is manufactured by pressure sintering, for example, hot pressing (HP), spark plasma sintering (SPS) or hot hydrostatic pressing (HIP). A sintered compact can be manufactured by this.

When performing the pressure sintering process in this step as described above it is preferable to perform the sintering at a temperature of 350 ~ 500 ℃ and a pressure of 30 ~ 80 MPa.

As a specific example of this step, a Bi-Sb-Te alloy-CNT (or CNT including metal coating layer) composite thermoelectric material manufacturing process through discharge plasma sintering will be described below.

The discharge plasma sintering process is a process in which a powder is filled into a mold, mounted in a vacuum chamber of a discharge plasma sintering apparatus, and sintered to a desired size by applying pressure and a direct current pulse to the powder. Due to the above instantaneous high energy, the surface of the alloy powder is melted and the powder is sintered without oxidation, thereby effectively controlling the growth of the powder particles, thereby sintering in a short time to maintain the microstructure.

In order to manufacture a Bi-Sb-Te alloy-CNT (or CNT with a metal coating layer) composite thermoelectric material through a discharge plasma sintering process, a cylindrical mold having a diameter of 15 to 25 φ and a thickness of 5 to 7 mm was prepared. The Bi-Sb-Te-based alloy-CNT composite powder or Bi-Sb-Te-based alloy-CNT composite powder containing a metal coating layer is filled in the above, and the mold is mounted in a chamber of a discharge plasma sintering apparatus, and the pressure is reduced and then pressurized. While applying a DC pulse using a pulsed DC generator.

At this time, to remove the oxidizing gas existing in the chamber can be reduced to less than 10 ^-3 torr, the DC pulse can be applied in the range of 0.1 ~ 2000A.

Subsequently, the composite thermoelectric material powder filled in the mold is uniaxially compressed at a pressure of 30 to 80 MPa by using a punch at the top and the bottom thereof. If the sintered compact is difficult to produce and exceeds 80 MPa, cracks may occur in the sintered compact after the sintering process is completed.

In addition, with respect to the sintering temperature and the sintering time, the sintering may be performed at 350 to 500 ° C. for 10 to 1800 seconds at a heating rate of 35 to 45 ° C./min, which is sintered at the surface of the powder particles at a temperature lower than 350 ° C. This is because the unsintered portion is not generated and the sintered compact is crushed as the strength of the sintered compact is low, and grain growth due to recrystallization occurs at a temperature higher than 500 ° C., making it difficult to refine the grains constituting the sintered compact.

The sintered body manufactured through discharge plasma sintering as described above has fine grains by increasing density and suppressing grain growth, thereby improving thermoelectric performance by excellent mechanical properties such as hardness and reducing thermal conductivity by phonon scattering.

According to the manufacturing method of the CNT-containing Bi-Sb-Te-based thermoelectric material according to the present invention described above, mass production is possible by applying a mechanical alloying process by high energy milling, which is a powder metallurgy process technology, for the production of the thermoelectric material. By incorporating carbon nanotubes (CNT) with metal coating layers into Bi-Sb-Te thermoelectric materials through mechanical alloying, the electrical conductivity is increased while the thermal conductivity is suppressed, which is superior to the existing thermoelectric materials. Of course, it is possible to manufacture a thermoelectric material having improved mechanical properties.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Embodiments according to the present disclosure may be modified in many different forms, and the scope of the present disclosure is not to be construed as limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

<Example>

467.9 g of bismuth (Bi), 818.06 g of antimony (Sb), and 1774.03 g of tellurium (Te) were weighed into a graphite crucible and subjected to high frequency induction melting at a pressure of 5 × 10 ⁻³ torr and a temperature of 750 ° C.

When the temperature of the material reaches 750 ℃, the molten alloy molten metal freely falls through an orifice of 5 mm in diameter, and the high-pressure argon gas injected through the spray nozzle and the free-falling molten metal spray impinge upon the flow of liquid. Fractured and solidified rapidly to produce a fine Bi-Sb-Te alloy powder.

BiSbTe / CNT composite powder and BiSbTe / Cu-CNT composite powder uniformly dispersed using a milling process after adding CNT or CNT (Cu-CNT) including a copper coating layer to the Bi-Sb-Te alloy powder prepared as described above Was prepared. When preparing the composite powder, the content of CNT was 2 wt% based on the total weight of the composite powder, and the mixing process was prepared in an inert atmosphere (Ar). The material of the container and the ball used in this process was set to ZrO ₂ , and the ratio of the ball and the powder was set to 10: 1. After the charging of the powder was completed, high-energy milling was performed. At this time, the milling speed was set to 1100 RPM and the milling time was set to 20 minutes.

FIG. 2 is a scanning electron microscope (SEM) photograph showing the shape of BiSbTe thermoelectric powder (left photograph) and BiSbTe thermoelectric composite powder (right photograph) in which CNTs are combined. Referring to this, BiSbTe + CNT composite is compared with BiSbTe powder having a clean surface. It can be seen that CNTs are dispersed on the surface of the powder.

(I) Bi-Sb-Te alloy powder obtained as described above, (ii) composite powder of Bi-Sb-Te alloy powder and CNT, and (iii) composite powder of Bi-Sb-Te alloy powder and Cu-CNT, respectively. A cylindrical mold having a diameter of 20 φ and a thickness of 6 mm was filled and maintained at a pressure of 50 Mpa in a vacuum atmosphere of 10 ⁻³ torr, and heated at a heating rate of 40 ° C./min for 10 minutes to reach a final temperature of 400 ° C. When the temperature reaches 400 ° C., it is cooled in a furnace for 5 minutes while maintaining a pressure of 50 MPa, and a sintered body having a diameter of 20 φ and a thickness of 6 mm (sintered body (BST) manufactured by Bi-Sb-Te alloy powder, Bi- A sintered body (BST + CNT) made from a composite powder of Sb-Te alloy powder and CNT and a sintered body (BST + Cu-CNT) made from a composite powder of Bi-Sb-Te alloy powder and Cu-CNT) was prepared.

The following table shows the density and hardness of each of the sintered bodies, and the density of the sintered bodies showed a tendency to decrease with the addition of CNT, which is judged to be due to the generation of internal micropores due to the low density of CNTs and reduced moldability. , The hardness of the sintered body showed a tendency to increase with the addition of CNTs.

Figure 3 shows the results of measuring the change in electrical properties of Bi-Sb-Te-based thermoelectric material according to the addition of CNTs.

Figure 3 (a) is the Seebeck coefficient measurement results for each sintered body, referring to this, the Seebeck coefficient of BiSbTe and BiSbTe + CNT increases up to 350 ~ 400K and then decreases, whereas BiSbTe + Cu-CNT increases in temperature As it increased to 500K. Therefore, BST + Cu-CNT had a low Seebeck coefficient at room temperature, but it was confirmed that the Seebeck coefficient of the BiSbTe + Cu-CNT sintered body was higher than that of the BiSbTe material at 450K or higher.

In addition, Figure 3 (b) shows a general tendency to decrease as the temperature increases as a result of the electrical conductivity of the thermoelectric sintered body, in particular, when CNT is added to BiSbTe, the electrical conductivity is lowered, but Cu-CNT is added In the material, it showed an increase of about 2 times that of the existing BiSbTe sintered body and about 3 times that of the BiSbTe + CNT material.

)를 계산했을 때 BiSbTe+Cu-CNT의 물성은 고온영역으로 감에 따라 다른 소재보다 상대적으로 우수할 것으로 판단된다.Based on the result according to FIG.

), The properties of BiSbTe + Cu-CNT are considered to be superior to other materials as it moves to high temperature range.

4 (a) shows the results of measurement of lattice thermal conductivity of each sintered body, which shows that lattice thermal conductivity was decreased according to the addition of CNT, and in particular, the material added with Cu-CNT decreased more than twice as much as the thermoelectric material added with CNT. Indicated.

On the other hand, in the case of the electronic thermal conductivity measurement results shown in Figure 4 (b), it has a value depending on the electrical conductivity, from which BST + Cu-CNT is the highest electron due to the high electrical conductivity value due to the addition of Cu-CNT It was confirmed that it had thermal conductivity.

Figure 4 (c) shows the results of the thermal conductivity of each sintered body, the thermal conductivity can be represented by the sum of the lattice thermal conductivity (a) and the electron thermal conductivity (b), the thermal conductivity of BST + CNT is not added CNT The temperature dependence was about 25% lower than that of one material (BST), and the temperature dependence showed the same tendency of increasing the thermal conductivity with increasing temperature. In the case of BST + Cu-CNT, the thermal conductivity was similar to that of the unadded sample due to the high electron thermal conductivity and the low lattice thermal conductivity at room temperature, but as the temperature increases, the BST + Cu-CNT has a constant value almost unchanged due to the low lattice thermal conductivity. In the high temperature region, the thermal conductivity is lower than that of other materials.

5 is a comparison result of the thermoelectric performance index (ZT) of the thermoelectric material sintered bodies (BST, BST + CNT and BST + Cu-CNT) prepared in the Examples of the present application. Referring to FIG. 5, at room temperature (300K) Thermal conductivity was decreased at, and BiSbTe + CNT showed lower performance than that of sintered body without CNT due to the reduced Seebeck coefficient and electrical conductivity.

On the other hand, BiSbTe + CNT has lower physical properties than the conventional materials at 300K, but as the temperature increases, the ZS value of about 1.1 is obtained at 450K due to the high electrical conductivity and low thermal conductivity, which is the highest physical properties of BiSbTe material. This is equivalent to about 20% improvement.

Therefore, when Cu-CNT is added, it is confirmed that the thermal conductivity can be effectively increased by suppressing the increase in thermal conductivity while increasing the electrical conductivity.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention belongs may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. You will understand that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

Claims (8)

(a) complexing (i) Bi-Sb-Te-based thermoelectric powders and (ii) carbon nanotubes having carbon nanotubes (CNTs) or metal coating layers through high energy milling; And
(b) manufacturing a sintered body from the composite powder obtained in step (b); and a method for producing a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material. The method of claim 1,
In the step (a), the Bi-Sb-Te-based thermoelectric powder is Bi _0.5 Sb _1.5 Te ₂ , characterized in that the carbon nanotube-containing Bi-Sb-Te-based thermoelectric material manufacturing method. The method of claim 1,
In the step (a), the metal coating layer is a method of producing a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material, characterized in that made of copper (Cu), silver (Ag) or aluminum (Al). The method of claim 1,
The composite powder obtained in the step (a) is a carbon nanotube-containing Bi-Sb-Te-based thermoelectric material, characterized in that containing 0.1 to 5.0% by weight of carbon nanotubes. The method of claim 1,
Carbon nanotube-containing Bi-Sb- characterized in that high energy milling is performed using planetary ball milling, attrition milling or shaker milling in step (a). Te-based thermoelectric material manufacturing method. The method of claim 1,
Carbon nanotube-containing Bi, characterized in that the sintered body is prepared by hot pressing (Hot Pressing, HP), discharge plasma sintering (SPS) or hot isostatic pressing (HIP) in step (b) -Sb-Te based thermoelectric material manufacturing method. The method of claim 1,
The carbon nanotube-containing Bi-Sb-Te-based thermoelectric material, characterized in that the sintering is carried out at a temperature of 350 ~ 500 ℃ and pressure of 30 ~ 80 MPa in the step (b). A carbon nanotube-containing Bi-Sb-Te-based thermoelectric material produced by the method according to any one of claims 1 to 7.

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