CN110880547B - Thermoelectric composite material and preparation method thereof - Google Patents
Thermoelectric composite material and preparation method thereof Download PDFInfo
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N10/00—Thermoelectric devices comprising a junction of dissimilar materials, i.e. devices exhibiting Seebeck or Peltier effects
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- H10N10/85—Thermoelectric active materials
- H10N10/851—Thermoelectric active materials comprising inorganic compositions
- H10N10/855—Thermoelectric active materials comprising inorganic compositions comprising compounds containing boron, carbon, oxygen or nitrogen
Abstract
The invention provides a thermoelectric composite material and a preparation method thereof, wherein the thermoelectric composite material comprises Cu 2‑x Zn x Se and graphene; the value of x is 0.2-1. According to the thermoelectric composite material provided by the invention, the thermoelectric performance of the thermoelectric composite material is improved by doping Zn and graphene. The experimental results show that: the thermoelectric composite material reaches the maximum value at 750 ℃, and the ZT value of the thermoelectric composite materials with different compositions is 1.27-1.49.
Description
Technical Field
The invention belongs to the technical field of thermoelectric materials, and particularly relates to a thermoelectric composite material and a preparation method thereof.
Background
The activities of human beings and the development of society are not separated from the utilization of energy, from the supporting strength in the aerospace field to the service systems of illumination, traffic, catering, heating, cooling and the like in the life of the human beings, the energy permeates into the society, the energy is promoted to be an economic improvement and a social improvement, and the energy can be called the blood of the modern human society. Since the rapid development of industrialization, humans have produced large amounts of non-renewable energy sources such as coal, oil, and natural gas. According to incomplete statistics, in the current age of rapid development of the industrialization process, by 2004, human social activities have consumed nearly 50% of petrochemical resources on the earth, and the earth's home is experiencing an irreducible energy pressure. The rapid increase in resource consumption has become a serious challenge for worldwide international sustainable development. In addition, in the present industrialized society, a large amount of energy is discharged in the form of waste heat, exhaust gas and automobile exhaust gas in the process of utilization while the energy is used by human beings in a large amount from time to time. The energy cannot be efficiently utilized, and meanwhile, the problem of environmental pollution is brought, and the problems of energy crisis and environmental pollution are solved, so that wide attention is paid internationally. In a new era where the problem between energy and environment is increasingly prominent, people are continually striving to develop clean energy, such as solar energy, wind energy and geothermal energy, so as to reduce the consumption of non-renewable energy and simultaneously alleviate the problem of environmental pollution caused by energy consumption.
Thermoelectric materials are a clean novel energy material, and are functional materials capable of realizing heat and electricity interconversion by utilizing thermoelectric conversion technology. In the society of sustainable development today, thermoelectric materials are favored as green and environment-friendly novel functional materials. Thermoelectric materials realize power generation and refrigeration through the transportation of carriers (holes and electrons) in the materials, and the working principle gives the materials the advantages which are not comparable with other materials: the working does not need mechanical rotation, has no noise, no pollution, small size and long service life. Thermoelectric performance is described in terms of "thermoelectric figure of merit": zt= (σa2/K) T. σ is the electrical conductivity, α is the seebeck coefficient, K is the thermal conductivity, and T is the temperature. The higher the ZT value, the better the performance of the material and the higher the thermoelectric conversion efficiency. The human beings hope that the materials can utilize a large amount of waste heat generated by industry and agriculture as a heat source, and then circularly convert the waste heat into electric energy, and the construction of the ambitious blueprint shows great social value and commercial value. The thermoelectric device made of the thermoelectric material can convert heat energy into electric energy within a given temperature difference range, and the characteristics enable the thermoelectric material to meet the requirements of the fields with special restrictions such as aerospace, ocean engineering and field operation.
The Cu-based thermoelectric material with the diamond-like structure is widely focused as a novel thermoelectric material, and the complex crystal structure endows the novel thermoelectric material with lower specific heat, so that the novel thermoelectric material has lower thermal conductivity. In addition, the compound with the structure also has adjustable and controllable electrical property. The advantages make it one of thermoelectric materials with great development potential in medium-high temperature areas. Cu (Cu) 2 Se is a recently discovered class of thermoelectric material systems for which conduction is primarily dependent on cu+ ions, known as a super-ionic conductor material. Having Cu + Ion-deficient Cu 2 The conductivity of Se materials is generally very high and can reach 10 2 ～10 3 S·cm -1 And the thermal conductivity is not high, so that the thermoelectric performance is better.
Fan et al in the prior artStudy of Cu by hot-press discharge plasma sintering method 2 Ga x Sn 1-x Se 3 The thermoelectric properties of diamond-like composite materials, the Sn sites being doped with Ga, have been studied mainly for Cu by two different preparation processes, hot-pressed sintering (HP) and Spark Plasma Sintering (SPS) 2 Ga x Sn 1-x Se 3 The influence of thermoelectric properties has been found that with the SPS process, HP causes a more uniform distribution of Ga in the matrix, and different sintering processes do not have a significant influence on the concentration of carriers, but a higher carrier concentration is obtained in samples with a more uniform distribution of Ga. The thermoelectric figure of merit obtained by HP sintering is about 15% -35% higher than that obtained by SPS sintering.
Shi et al propose a filled skutterudite thermoelectric material having a Cu-Se framework similar to that in PGEC, mainly comprising a Cu-Se framework filled with Sn atoms, cu 2 SnSe 3 The structural compound has lower thermal conductivity and adjustable electric property. Cu doping with In has also been reported 2 Sn 1-x In x Se 3 Carrier concentration is adjusted to obtain higher conductivity, when x=0.1, cu 2 Sn 0.9 In 0.1 Se 3 The maximum ZT value of 1.14 is obtained at 700K.
Disclosure of Invention
In view of the above, the present invention is directed to a thermoelectric composite material and a method for preparing the same, wherein the composite material has high thermoelectric performance.
The invention provides a thermoelectric composite material comprising Cu 2-x Zn x Se and graphene;
the value of x is 0.2-1.
Preferably, x is 0.2, 0.4, 0.6, 0.8 or 1.
Preferably, the graphene occupies Cu 2-x Zn x 5 to 6 weight percent of Se.
The invention provides a preparation method of the thermoelectric composite material, which comprises the following steps:
mixing and ball milling copper powder, se powder, zinc oxide powder and graphene powder to obtain mixed powder;
and (3) carrying out plasma sintering at 500-850 ℃ after the mixed powder is pressed and formed, and preserving heat for 12-18 min to obtain the thermoelectric composite material.
Preferably, the granularity of the zinc oxide powder is 10-500 nm.
Preferably, the rotation speed of the ball mill is 450-550 rpm; the ball milling time is 8-12 h.
Preferably, the temperature is increased to 500-850 ℃ at a heating rate of 28-30 ℃/min for plasma sintering.
Preferably, the plasma sintering is performed under vacuum conditions with a total gas pressure of less than 6 Pa.
Preferably, an axial pressure of 100 to 150MPa is applied to the mixed powder during the press molding.
The invention provides a thermoelectric composite material comprising Cu 2-x Zn x Se and graphene; the value of x is 0.2-1. According to the thermoelectric composite material provided by the invention, the thermoelectric performance of the thermoelectric composite material is improved by doping Zn and graphene. The experimental results show that: the thermoelectric composite material reaches the maximum value at 750 ℃, and the ZT value of the thermoelectric composite materials with different compositions is 1.27-1.49.
Drawings
FIG. 1 is a process flow diagram for preparing a thermoelectric composite provided by the present invention;
FIG. 2 is a scanning electron microscope image at 3000 times of the thermoelectric composite prepared in example 1 of the present invention;
FIG. 3 is an EDS diagram of a thermoelectric composite prepared in example 1 of the present invention;
FIG. 4 is a scanning electron microscope image of a region of the thermoelectric composite prepared in example 1 of the present invention at 500 times magnification;
FIG. 5 is a scanning electron microscope image at 500 Xmagnification of another region of the thermoelectric composite prepared in example 1 of the present invention;
FIG. 6 shows ZT values of thermoelectric composite materials prepared in examples 1 to 5 of the present invention;
fig. 7 shows ZT values of thermoelectric composite materials of example 6 and comparative examples 1 to 3 according to the present invention.
Detailed Description
The invention provides a thermoelectric composite material comprising Cu 2-x Zn x Se and graphene;
the value of x is 0.2-1.
According to the thermoelectric composite material provided by the invention, the thermoelectric performance of the thermoelectric composite material is improved by doping Zn and graphene.
In the invention, the value of x is 0.2-1; preferably, the x=0.2, x=0.4, x=0.6, x=0.8 or x=1.0.
In the invention, the graphene preferably occupies Cu 2-x Zn x 5 to 6 weight percent of Se.
The invention provides a preparation method of the thermoelectric composite material, which comprises the following steps:
mixing and ball milling copper powder, se powder, zinc oxide powder and graphene powder to obtain mixed powder;
and (3) carrying out plasma sintering at 500-850 ℃ after the mixed powder is pressed and formed, and preserving heat for 12-18 min to obtain the thermoelectric composite material.
The invention combines zinc oxide and graphene to Cu by adopting a method of combining mechanical alloying with spark plasma sintering 2 ZnO is successfully introduced into skutterudite material as a second phase in Se matrix, and phonons in crystal structure can be scattered to reduce lattice heat conductivity of the composite material, so that thermoelectric performance is improved.
According to the invention, copper powder, se powder, zinc oxide powder and graphene powder are mixed and ball milled to obtain mixed powder. In the present invention, copper powder with a purity of 99.999% is preferably used as the copper powder; the Se powder is preferably Se powder with the purity of 99.99 percent; the zinc oxide powder is preferably zinc oxide powder with the purity of 99.99%; the zinc oxide powder is preferably nano-sized zinc oxide powder; the particle size of the zinc oxide powder is preferably 10-500 nm.
The present invention is preferably ball-milled using a ball mill well known to those skilled in the art. The grinding balls adopted during ball milling are zirconium oxide components; the mass ratio of the grinding balls to the mixed powder is 15:1. In the present invention, the rotation speed of the ball mill is preferably 450 to 550rpm, more preferably 480 to 520rpm, and most preferably 500rpm; the ball milling time is preferably 8 to 12 hours. The invention realizes the solid alloying process by ball milling. Mechanical alloying is a complex physicochemical process in which powders are subjected to repeated deformation, cold welding, and crushing by high-energy ball milling, thereby achieving inter-element atomic level alloying. In the invention, the mass of the graphene preferably accounts for 5-6% of the total mass of the copper powder, se powder and zinc oxide powder. The graphene plays a catalytic role in the sintering process.
After the mixed powder is obtained, the mixed powder is pressed and molded, then is subjected to plasma sintering at 500-850 ℃, and is subjected to heat preservation for 12-18 min, so that the thermoelectric composite material is obtained.
In the invention, the mixed powder is preferably placed in a graphite die for compression molding; the axial pressure of 100 to 150MPa is preferably applied to the mixed powder during the press molding.
The invention preferably performs sintering in a plasma sintering furnace; the sintering temperature is 500-850 ℃; the plasma sintering is preferably performed at a temperature rising rate of 28 to 30 ℃/min to 500 to 850 ℃, and more preferably at a temperature rising rate of 30 ℃/min. And (3) after the temperature is raised to the required sintering temperature, preserving the heat for 12-18 min, and preferably preserving the heat for 15min. The plasma sintering is performed under vacuum conditions with a total gas pressure of less than 6 Pa. After the end of the incubation, it is preferably cooled to room temperature with the furnace.
FIG. 1 is a process flow diagram for preparing a thermoelectric composite provided by the present invention; as can be seen from fig. 1, cu, se, znO and graphene are mixed, ball-milled, pressed and formed, and then SPS sintered to obtain a thermoelectric composite material.
In order to further illustrate the present invention, a thermoelectric composite and a method for preparing the same are described in detail below with reference to examples, but they should not be construed as limiting the scope of the present invention.
Example 1
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%) and ZnO powder (purity 99.99%) with granularity of 500nm according to a molar ratio of 1.4:1:0.6; the graphene powder (the purity is 99.999%) accounts for 5% of the total mass of the Cu powder, the Se powder and the zinc oxide powder, the graphene powder is placed in a sealed ball milling tank under protective atmosphere and is placed on a high-energy ball mill for ball milling, wherein the grinding balls are zirconia components, the mass ratio of the grinding balls to the mixture is 15:1, the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 h, so that mixed powder can be obtained;
placing the mixed powder into a steel mold, placing a steel mill into an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6pa, heating at the heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃, preserving heat for 15min, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material comprising Cu 1.4 Zn 0.6 Se and Cu are compounded 1.4 Zn 0.6 Graphene on Se.
The thermoelectric composite material prepared in the embodiment 1 is subjected to scanning electron microscope analysis and EDS analysis, the results are shown in fig. 2 and 3, and fig. 2 is a scanning electron microscope image of the thermoelectric composite material prepared in the embodiment 1 at 3000 times; FIG. 3 is an EDS diagram of a thermoelectric composite prepared in example 1 of the present invention; fig. 3 can be seen: the basic components of the thermoelectric composite material comprise Cu, zn, se and trace C elements; the composite material comprises Cu 1.4 Zn 0.6 Se。
FIG. 4 is a scanning electron microscope image of a region of the thermoelectric composite prepared in example 1 of the present invention at 500 times magnification; FIG. 5 is a scanning electron microscope image at 500 Xmagnification of another region of the thermoelectric composite prepared in example 1 of the present invention.
The thermoelectric composite material prepared in example 1 is subjected to measurement of thermoelectric figure of merit ZT, the result is shown in FIG. 6, and FIG. 6 shows ZT values of thermoelectric composite materials prepared in examples 1 to 5; wherein curve 1 is the thermoelectric figure of merit of the thermoelectric composite material prepared in example 1, it can be seen that the thermoelectric composite material prepared in example 1 has little variation in ZT value or even a tendency to decrease as the sintering temperature increases; the thermoelectric figure of merit was 1.49.
Example 2
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%), znO powder with granularity of 500nm (purity 99.99%), graphene powder (purity 99.999%) accounting for 5% of the total mass of the Cu powder, se powder and zinc oxide powder according to a molar ratio of 1.2:1:0.8, sealing a ball milling tank in a protective atmosphere, and placing the ball milling tank on a high-energy ball mill for ball milling, wherein grinding balls are zirconium oxide components, the mass ratio of the grinding balls to the mixture is 15:1, the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 h, so that mixed powder can be obtained;
placing the mixed powder into a steel mold, placing a steel mill into an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6pa, heating at the heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃, preserving heat for 15min, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material comprising Cu 1.2 Zn 0.8 Se and Cu are compounded 1.2 Zn 0.8 Graphene on Se.
The thermoelectric composite material prepared in example 2 was subjected to measurement of thermoelectric figure of merit ZT, and the result is shown in fig. 6, wherein curve 2 is the thermoelectric figure of merit of the thermoelectric composite material prepared in example 2, and it can be seen that the thermoelectric figure of merit of the thermoelectric composite material prepared in example 2 is 1.43.
Example 3
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%), znO powder with granularity of 500nm (purity 99.99%), graphene powder (purity 99.999%) accounting for 6% of the total mass of the Cu powder, se powder and zinc oxide powder according to a molar ratio of 1.6:1:0.4, sealing a ball milling tank in a protective atmosphere, and placing the ball milling tank on a high-energy ball mill for ball milling, wherein grinding balls are zirconium oxide components, the mass ratio of the grinding balls to the mixture is 15:1, the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 h, so that mixed powder can be obtained;
placing the mixed powder into a steel mold, placing a steel mill into an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6Pa, heating at the heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃ for 15min, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material comprising Cu 1.6 Zn 0.4 Se and Cu are compounded 1.6 Zn 0.4 Graphene on Se.
The thermoelectric composite material prepared in example 3 was subjected to measurement of thermoelectric figure of merit ZT, and the result is shown in fig. 6, wherein curve 3 is the thermoelectric figure of merit of the thermoelectric composite material prepared in example 3, and it can be seen that the thermoelectric figure of merit of the thermoelectric composite material prepared in example 3 is 1.32.
Example 4
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%), znO powder with granularity of 500nm (purity 99.99%), graphene powder (purity 99.999%) accounting for 5.5% of the total mass of the Cu powder, se powder and zinc oxide powder according to a molar ratio of 1.8:1:0.2, sealing a ball milling tank in a protective atmosphere, and ball milling on a high-energy ball mill, wherein grinding balls are zirconium oxide components, the mass ratio of the grinding balls to the mixture is 15:1, the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 h, so that mixed powder can be obtained;
placing the mixed powder into a steel mold, placing a steel mill into an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6Pa, heating at the heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃ for 15min, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material comprising Cu 1.8 Zn 0.2 Se and Cu are compounded 1.8 Zn 0.2 Graphene on Se.
The thermoelectric composite material prepared in example 1 was subjected to measurement of thermoelectric figure of merit ZT, and the result is shown in fig. 6, wherein curve 4 is the thermoelectric figure of merit of the thermoelectric composite material prepared in example 4, and it can be seen that the thermoelectric figure of merit of the thermoelectric composite material prepared in example 4 is 1.38.
Example 5
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%), znO powder with granularity of 500nm (purity 99.99%), graphene powder (purity 99.999%) accounting for 6% of the total mass of the Cu powder, se powder and zinc oxide powder according to a molar ratio of 1:1:1, sealing a ball milling tank in a protective atmosphere, placing the ball milling tank on a high-energy ball mill for ball milling, wherein grinding balls are zirconium oxide components, and the ball milling time is 8-12 h according to the mass ratio of the grinding balls to the mixture of 15:1, wherein the rotating speed of the ball mill is 500r/min, so that mixed powder can be obtained;
and (3) filling the mixed powder into a steel mold, placing a steel mill in an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6pa, heating at the heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material, wherein the thermoelectric composite material comprises CuZnSe and graphene compounded on the CuZnSe.
The thermoelectric composite material prepared in example 5 was subjected to measurement of thermoelectric figure of merit ZT, and the result is shown in fig. 6, wherein curve 5 is the thermoelectric figure of merit of the thermoelectric composite material prepared in example 5, and it can be seen that the thermoelectric figure of merit of the thermoelectric composite material prepared in example 5 is 1.27.
Example 6
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%), znO powder with granularity of 500nm (purity 99.99%), graphene powder (purity 99.999%) accounting for 0.5% of the total mass of the Cu powder, se powder and zinc oxide powder according to a molar ratio of 1.9:1:0.1, sealing a ball milling tank in a protective atmosphere, and ball milling on a high-energy ball mill, wherein grinding balls are zirconium oxide components, the mass ratio of the grinding balls to the mixture is 15:1, the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 h, so that mixed powder can be obtained;
placing the mixed powder into a steel mold, placing a steel mill into an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6pa, heating at the heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃, preserving heat for 15min, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material comprising Cu 1.9 Zn 0.1 Se and Cu are compounded 1.9 Zn 0.1 Graphene on Se.
The thermoelectric composite prepared in example 6 was measured for thermoelectric figure of merit ZT according to the present invention, and the result is shown in fig. 7, wherein curve 1 is the thermoelectric figure of merit of the thermoelectric composite prepared in example 6, and it can be seen that the thermoelectric figure of merit of the thermoelectric composite prepared in example 6 is 1.36.
Comparative example 1
Weighing Cu powder (purity 99.999%) and Se powder (purity 99.99%) according to a molar ratio of 2:1, sealing the materials in a ball milling tank under protective atmosphere, and placing the materials on a high-energy ball mill for ball milling, wherein the grinding balls are zirconia components, the mass ratio of the grinding balls to the mixture is 15:1, the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 hours, so that mixed powder can be obtained;
filling the mixed powder into a steel mold, placing a steel mold in an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6Pa, heating at the heating rate of 30 ℃/min, keeping the sintering temperature at 500-850 ℃ for 15min, and cooling to room temperature along with the furnace to obtain Cu 2 Se composite material.
Comparative example 1 of the present invention prepared Cu 2 Thermoelectric performance test was performed on Se composites, the results of which are shown in fig. 7, and fig. 7 shows ZT values of thermoelectric composites of example 6 and comparative examples 1 to 3 of the present invention; wherein curve 4 is Cu prepared in comparative example 1 2 As can be seen from FIG. 7, the ZT value of Se composite material, cu prepared in comparative example 1 2 The ZT value of the Se composite was 0.84. As seen from fig. 7: with the increase of sintering temperature, cu 2 Thermoelectric ZT values of Se-based composites all show an increasing trend due to the rising sintering temperature, cu 2 The Se alloying degree is gradually perfected, the unit cell grows up, and the microstructure is uniform; in Cu 2 The composite material with ZnO and graphene added into Se base has better ZT value, and the ZT value can reach 1.36 under the condition of 750 ℃.
Comparative example 2
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%), znO powder with granularity of 500nm (purity 99.99%) according to a molar ratio of 2:1:1, sealing the mixture in a ball milling tank under a protective atmosphere, placing the mixture on a high-energy ball mill for ball milling, wherein the grinding balls are zirconia components, the mass ratio of the grinding balls to the mixture is 15:1, the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 h, so that mixed powder can be obtained;
filling the mixed powder into a steel mold, placing a steel mold in an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6Pa, heating at the heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃, preserving heat for 15min, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material.
Comparative example 2 of the present invention 2 Thermoelectric performance test of Se composite material is shown in FIG. 7, wherein curve 2 is Cu prepared in comparative example 2 2 The ZT value of the Se composite was found to be 1.08 for the composite of comparative example 2.
Comparative example 3
Weighing Cu powder (purity 99.999%), se powder (purity 99.99%), and graphene powder (purity 99.999%) accounting for 5% of the total mass of the Cu powder and the Se powder according to a molar ratio of 2:1, sealing the ball milling tank in a protective atmosphere, and placing the ball milling tank on a high-energy ball mill for ball milling, wherein the components of the grinding ball are zirconium oxide, weighing the grinding ball according to a mass ratio of the grinding ball to the mixture of 15:1, wherein the rotating speed of the ball mill is 500r/min, and the ball milling time is 8-12 h, thus obtaining mixed powder;
and (3) filling the mixed powder into a steel mold, placing a steel mill in an SPS sintering furnace, applying 100-150 MPa axial pressure, sintering under the vacuum condition that the total air pressure is lower than 6pa, heating at a heating speed of 30 ℃/min, keeping the sintering temperature at 500-850 ℃, preserving heat for 15min, and cooling to room temperature along with the furnace to obtain the thermoelectric composite material.
Comparative example 3 of the present invention 2 Thermoelectric performance test of Se composite material is shown in FIG. 7, wherein curve 3 is Cu prepared in comparative example 3 2 The ZT value of the Se composite was found to be 0.96 for the composite of comparative example 3.
From the above examples, the present invention provides a thermoelectric composite material comprising Cu 2-x Zn x Se and graphene; the value of x is 0.2-1. According to the thermoelectric composite material provided by the invention, the thermoelectric performance of the thermoelectric composite material is improved by doping Zn and graphene. The experimental results show that: the thermoelectric composite material reaches the maximum value at 750 ℃, and the ZT value of the thermoelectric composite materials with different compositions is 1.27-1.49.
The foregoing is merely a preferred embodiment of the present invention and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present invention, which are intended to be comprehended within the scope of the present invention.
Claims (5)
1. A method of preparing a thermoelectric composite comprising the steps of:
mixing and ball milling copper powder, se powder, zinc oxide powder and graphene powder to obtain mixed powder;
after the mixed powder is pressed and molded, the temperature is increased to 500-850 ℃ at the heating rate of 28-30 ℃/min, the plasma sintering is carried out under the vacuum condition that the total air pressure is lower than 6Pa, and the temperature is kept for 12-18 min, so as to obtain the thermoelectric composite material;
the thermoelectric composite material comprises Cu 2-x Zn x Se and graphene;
the value of x is 0.2-1;
the graphene occupies Cu 2-x Zn x 5 to 6 weight percent of Se.
2. The method of claim 1, wherein x is 0.2, 0.4, 0.6, 0.8 or 1.
3. The process for preparing as claimed in claim 1, wherein the particle size of the zinc oxide powder is from 10 to 500nm.
4. The method according to claim 1, wherein the rotational speed of the ball mill is 450 to 550rpm; the ball milling time is 8-12 h.
5. The method according to claim 1, wherein an axial pressure of 100 to 150MPa is applied to the mixed powder during the press molding.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103817466A (en) * | 2014-02-26 | 2014-05-28 | 哈尔滨工业大学 | Method for efficiently preparing graphene-reinforcing copper-based composite brazing filler metal at low temperature |
| CN105215353A (en) * | 2015-11-09 | 2016-01-06 | 山东大学 | A kind of Metal/grapheme composite and preparation method thereof |
-
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103817466A (en) * | 2014-02-26 | 2014-05-28 | 哈尔滨工业大学 | Method for efficiently preparing graphene-reinforcing copper-based composite brazing filler metal at low temperature |
| CN105215353A (en) * | 2015-11-09 | 2016-01-06 | 山东大学 | A kind of Metal/grapheme composite and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 宁纪爱.Cu2SnSe3基热电复合材料的制备与性能研究.中国优秀硕士学位论文全文数据库.2018,摘要、第3.6章. * |
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