212 results about "Bismuth telluride" patented technology

The invention relates to the field of electric heating materials, and provides a graphene-based heating coating and a preparation method thereof. The coating is prepared from functionalized graphene, a surface modified bismuth telluride nanobelt, polyaniline, bisphenol A epoxy acrylate, polyurethane acrylate, a dispersing agent, a flatting agent, a silane coupling agent, a defoaming agent and a propylene glycol methyl ether acetate / N-methyl pyrrolidone mixed solvent. The functionalized graphene is obtained by modifying a hyperbranched polyolefin-acryloyl-POSS copolymer, and carrying out ultrasonic stripping, centrifugal separation, gradient washing and vacuum drying; the surface-modified bismuth telluride nanobelt is modified by an amino silane coupling agent, so that the interfacial compatibility is improved. The preparation method comprises the steps of solvent premixing, nanofiller dispersion, ultrasonic homogenization, coupling agent modification, ultraviolet curing and thermocuring. The heating coating provided by the invention has high conductivity, excellent thermal stability and adhesive force, and can be widely applied to heating electric appliances and intelligent temperature control equipment.

The invention relates to the technical field of infrared sensors, in particular to a monolithic integrated MEMS out-of-plane thermopile chip and a preparation method thereof, and the thermopile chip comprises a substrate, and a bottom electrode, a thermocouple array, a top electrode and an optical radiation absorption layer which are sequentially arranged on the substrate; the thermocouple array is vertically arranged on the bottom electrode; the thermocouple array comprises a plurality of thermocouple pairs, and each thermocouple pair comprises an N-type thermocouple and a P-type thermocouple; the N-type thermocouple and the P-type thermocouple form a current and heat flow loop in an electric series connection and heat parallel connection mode. According to the invention, the bismuth telluride-based thermoelectric material with low thermal conductivity and high Seebeck coefficient difference is used as the thermocouple material of the out-of-plane thermopile chip, the heat conduction path of the out-of-plane thermopile chip is more direct, the temperature difference in the vertical direction can be directly utilized, and the higher response speed and high sensitivity are expected to be realized due to the more efficient thermal gradient.

The invention discloses a bismuth telluride nanopore maskless direct writing preparation method based on electron beam irradiation, and belongs to the technical field of nanometer manufacturing. The method comprises the following steps: firstly, constructing an initial nanopore in a two-dimensional bismuth telluride material by utilizing a converged electron beam; and then the aperture size of the nanopore is accurately regulated and controlled by adjusting the beam density of the electron beam. The method effectively solves the key technical bottlenecks of interface chemical residue pollution caused by a traditional photoresist mask process, intrinsic defect formation caused by high-energy particle bombardment and the like, and breaks through the limitation of an existing etching technology in the aspect of sub-nanoscale structure precision control; precise control of the aperture of the nanopore can be achieved by adjusting the irradiation intensity of the electron beam, and the method has the advantages of being easy and convenient to operate, low in cost, environmentally friendly and the like and can be widely applied to the fields of nanometer electronic devices, sensors and the like.

The invention relates to the field of thermoelectric semiconductor materials, and provides a method for improving the thermoelectric performance of a P-type extruded bismuth telluride-based material in order to solve the problems that the performance of a P-type material prepared through an optimized extrusion method is complex and the requirement for a device is high, the method comprises the following steps that (1) the bismuth telluride-based material is smashed into powder, and the particle size range of the powder is D50gt; 150 [mu] m, D90lt; 2000 [mu] m; and (2) carrying out compression molding, sintering, hot extrusion and annealing on the powder to obtain the P-type extruded bismuth telluride-based material. According to the method, the particle size of the powder before extrusion is controlled within a reasonable range, and the comprehensive performance of lattice thermal conductivity and mobility of the bismuth telluride-based material after extrusion is optimal, so that the thermoelectric performance of the extruded material is improved.

The invention discloses a method for preparing a strong-texture bismuth telluride-based thermoelectric material through construction molding, and the method specifically comprises the steps: respectively weighing Bi, Te and Sb elementary substances according to a design ratio, crushing the Bi, Te and Sb elementary substances into fine powder, sieving the fine powder, and carrying out ball-milling mixing to obtain a mixed material; dividing the obtained mixed material into two equal parts, and carrying out sintering molding by adopting spark plasma sintering equipment, so as to obtain a No.1 sintering blank and a No.2 sintering blank which are the same in size; carrying out mechanical grinding and polishing on one surface of the obtained blank to form a mirror surface; and putting the treated mirror surfaces into a mold in a contact manner, and sintering and molding by using spark plasma to obtain the constructed and molded strong-texture thermoelectric material. The method has the beneficial effects that through two times of spark plasma sintering, sufficient diffusion of alloy elements is facilitated, so that the traditional melting alloying step is omitted, the production efficiency is improved, and the cost is saved. Meanwhile, the orientation consistency of the thermoelectric material can be greatly improved through the secondary sintering forming technology, and the strong-texture thermoelectric material is obtained.

The invention discloses a preparation method of a bismuth telluride-based thermoelectric material and an extrusion die. A die groove of the extrusion die comprises an inlet section, a connecting section and an outlet section which are connected in sequence; the connecting section sequentially comprises a plurality of reducing sections from the inlet section to the outlet section; the diameter of the outlet end of any one of the multiple reducing sections is larger than that of the outlet end of the next reducing section. By improving orientation in a traditional hot extrusion process, the bismuth telluride-based thermoelectric material with high mechanical performance and high thermoelectric performance is prepared, and the problems of low mechanical strength, non-uniform deformation and the like in the preparation process of the traditional bismuth telluride-based thermoelectric material are solved.

The invention provides a preparation method of a zirconium oxide-doped bismuth telluride-based thermoelectric material, a nano zirconium oxide material is introduced to prepare the composite bismuth telluride-based thermoelectric material, and due to the outstanding electrical properties and mechanical properties of nano zirconium oxide, the thermoelectric properties and mechanical properties of a composite product are improved by ball-milling mixing and hot extrusion preparation processes. Compared with a commercial bismuth telluride material, the bismuth telluride material is improved. By doping the nano zirconia material, more stress can be effectively borne, the matrix load is reduced, the mechanical property of the material is improved, the thermoelectric property of the material is not reduced, and the application prospect of the bismuth telluride thermoelectric material is effectively widened.

The invention relates to the technical field of thermoelectric material surface treatment, and provides a bismuth telluride-based thermoelectric material wafer surface treatment method which comprises the following steps: acquiring multi-dimensional data such as current density distribution, temperature field distribution, solution concentration gradient and plating thickness increment in real time through a sensor array; performing iterative calculation on the data based on a thermoelectric performance parameter optimization model to generate an optimal parameter combination of chemical oil removal, activation, nickel plating and tin and bismuth plating processes; dynamically adjusting the anode plate area ratio, the current density threshold value and the solution temperature fluctuation range of the electroplating equipment; a self-adaptive feedback mechanism is used for correcting parameter deviation, so that a uniform thermoelectric function layer structure is formed on the surface of the wafer. According to the method, the uniformity and the thermoelectric performance stability of the surface coating of the bismuth telluride thermoelectric wafer can be improved, the defect rate is reduced, and the production efficiency and the product consistency are improved.

The invention relates to the field of thermoelectric materials, in particular to a preparation method of a bismuth telluride protective coating, which comprises the following steps: (1) immersing bismuth telluride into a chemical etching agent for chemical etching, dust removal and cleaning; (2) mixing the bismuth telluride treated in the step (1) with an energizing material; (3) putting the bismuth telluride and the energizing material into a chemical plating solution together for chemical plating, wherein the bismuth telluride, the energizing material and the chemical plating solution form a primary battery during the chemical plating; and cleaning to obtain the bismuth telluride with the protective coating. By applying continuous and stable weak voltage to the surfaces of the bismuth telluride crystal grains, autocatalysis of the bismuth telluride crystal grains is realized, the catalytic efficiency is high, the preparation process is simple, and the binding force and uniformity of a chemical plating layer can be improved so as to enhance the protection effect of bismuth telluride.

The invention provides a p-type bismuth telluride-based material and a preparation method and application thereof, and belongs to the technical field of thermoelectric energy conversion materials. The p-type bismuth telluride-based material comprises a base material and a Bi element doped into crystal lattices of the base material; the base material comprises BiaSb1. 45Te3, and a is greater than or equal to 0.55 and less than or equal to 0.58. The thermoelectric performance and the mechanical performance of the material are improved by introducing the Bi element (electronegativity 2.02) which has a small electronegativity difference with the Te element (electronegativity 2.1), and the small electronegativity difference enables the Bi element in a matrix to have higher solubility, so that the carrier concentration (the doping of the Bi element mainly optimizes the carrier concentration) and the density of the material are improved; and the increase of the carrier concentration can improve the conductivity, so that the thermoelectric performance is improved.

The invention discloses a thermoelectric sheet, a preparation method thereof and a box girder bridge capable of generating power through temperature difference energy, and the thermoelectric sheet comprises a copper-clad ceramic upper substrate, a copper-clad ceramic lower substrate, a geopolymer bismuth telluride P-type thermoelectric particle column, a geopolymer bismuth telluride N-type thermoelectric particle column and a wire. The geopolymer bismuth telluride P-type thermoelectric particle columns and the geopolymer bismuth telluride N-type thermoelectric particle columns which are connected with each other and distributed in an array mode are arranged between the copper-clad ceramic upper substrate and the copper-clad ceramic lower substrate, and the wires are connected with the geopolymer bismuth telluride N-type thermoelectric particle columns at the head end and the tail end. According to the bridge deck combined with the thermoelectric piece, generated electric energy can be used for self-monitoring and maintenance, and the service life of a bridge is prolonged; the thermoelectric sheet can convert heat absorbed by the bridge deck into electric energy and provide renewable energy, so that energy waste is reduced, energy can be provided for illumination, monitoring and other systems of the bridge, dependence on an external power supply is reduced, maintenance cost is reduced, and multifunctional integration is realized.

The invention discloses a preparation method of an N-type bismuth telluride-based thermoelectric thin film. The preparation method comprises the following steps: obtaining a bismuth raw material, a tellurium raw material and a selenium raw material; the preparation method comprises the following steps: smelting, grinding and sintering a bismuth raw material, a tellurium raw material and a selenium raw material to obtain an N-type bismuth-tellurium-selenium-based block target material; the N-type bismuth-tellurium-selenium-based block target material is deposited on a substrate through magnetron sputtering equipment, so that a bismuth-tellurium-selenium-based thin film is obtained; the N-type bismuth-tellurium-selenium-based block target material is deposited on a substrate through high-vacuum thermal evaporation equipment, so that a homogeneous-layer bismuth-tellurium-selenium-based thin film is obtained; according to the preparation method, the homogeneous layer bismuth-tellurium-selenium-based thin film is subjected to annealing treatment to obtain the N-type bismuth telluride-based thermoelectric thin film, and due to the fact that the method for preparing the bismuth-tellurium-selenium-based thin film through magnetron sputtering equipment and the method for preparing the bismuth-tellurium-selenium-based thin film through high-vacuum thermal evaporation equipment are combined, the high-performance N-type bismuth telluride-based thermoelectric thin film is obtained.

The invention relates to a preparation process of nano bismuth telluride, and belongs to the technical field of preparation of nano bismuth telluride, and the preparation process comprises the following steps: preparing a bismuth-based metal organic framework; carrying out coordination conversion on tellurate; calcining to remove organic conversion; and synthesizing bismuth telluride by a solvothermal method. The hexagonal flaky bismuth telluride with the average particle size of 200-300nm and reasonable particle size step-by-step is prepared through metal organic framework templating synthesis, the thermoelectric performance of the hexagonal flaky bismuth telluride is far better than that of a common bismuth telluride material, and the morphology and the particle size of the bismuth telluride are accurately controlled through metal organic framework templating accurate control so as to improve the thermoelectric performance of the bismuth telluride.

Disclosed in the present disclosure are a P-type bismuth telluride-based material and a method for preparing the P-type bismuth telluride-based material. The P-type bismuth telluride-based material is doped with a rare earth element, and prepared from a rare earth material, a Sb source, a Te source and a Bi source by melting, ball milling and sintering. An outer layer atomic orbital of the rare earth element can greatly improve the energy band structure of a matrix phase. At the same time, a large atomic difference between a rare earth atom and a Sb atom is utilized to provide a mass potential field, enhancing the phonon scattering probability, and reducing lattice thermal conductivity, and the double action of the rare earth element synergistically enhances the thermoelectric performance of the P-type bismuth telluride-based material.

The invention provides a method for measuring the performance of a multi-stage semiconductor cooler. The method comprises the following steps: determining a calculation equation of the performance of the multi-stage semiconductor cooler; when the geometrical parameters of the multistage TEC and the material characteristic parameters of the used gradient bismuth telluride are known, the electric performance parameters of the multistage semiconductor cooler are obtained through the equation; and when the electrical performance parameters of the multistage TEC are known, the geometric parameters of the multistage semiconductor cooler and the material characteristic parameters of the used gradient bismuth telluride are obtained through reverse inference by using the equation. The method has the beneficial effects that according to the calculated electrical performance parameters of the multistage TEC, an optimized multistage TEC use scheme for the load needing temperature control can be formed; the most appropriate bismuth telluride material is selected through guidance of a calculation result, so that the purposes of effectively reducing the material cost and meeting the high-standard temperature control requirement are achieved; a rapid design method is provided, through simulation calculation and a cyclic exhaustion method, a design scheme meeting performance requirements can be found in a short time, and trial and error time and cost in traditional design are reduced.

The invention relates to the technical field of thermoelectric material performance testing, and provides a method and equipment for measuring performance characterization parameters of a bismuth telluride-based thermoelectric material.The method comprises the steps that firstly, statistical analysis is conducted on geometrical parameters of a material sample, and the distribution proportion of different geometrical shapes is determined; then selecting test samples from the material database to construct a test sample set, and ensuring that the distribution proportion of different geometric forms in the sample set is consistent with a statistical analysis result; and generating a thermoelectric parameter measurement instruction based on the test sample set, carrying out performance test on the material by using the instruction, and collecting data through the test process to finally obtain the performance parameter data of the bismuth telluride-based thermoelectric material. According to the invention, the accuracy, stability and test efficiency of performance parameter measurement of the bismuth telluride-based thermoelectric material can be improved.

The invention provides a barrier layer for a bismuth telluride-based thermoelectric device, the bismuth telluride-based thermoelectric device and a preparation method and application of the bismuth telluride-based thermoelectric device, and relates to the technical field of thermoelectric devices. Materials adopted by the barrier layer for the bismuth telluride-based thermoelectric device comprise NiSbTe3, and due to the fact that NiSbTe3 is one of thermodynamic stable phases of a Bi2 / (Se, Te) 3-NiSbTe3-Sb2Te3 phase region, NiSbTe3 does not react with a bismuth telluride thermoelectric material at an interface to generate other harmful impurity phases at the temperature of 473 K or above; in addition, the intrinsic resistivity of NiSbTe3 is low, the linear thermal expansion coefficient of NiSbTe3 is close to that of bismuth telluride, and the barrier layer prepared through sintering and the bismuth telluride material have the advantages of being high in binding force, low in contact resistivity and the like. The bismuth telluride-based thermoelectric device adopting the NiSbTe3 barrier layer has excellent thermoelectric conversion performance and extremely excellent thermal stability.

The invention relates to the technical field of semiconductor material thermoelectric performance testing, in particular to a bismuth telluride sheet material Seebeck coefficient measuring device. The device mainly comprises a flexible measuring device and a data acquisition system, the data acquisition system is provided with a universal meter and a programmable power supply, the flexible measuring device is connected to the input end of the universal meter through a signal cable to transmit temperature and pressure signals of a thermocouple, and the flexible measuring device is connected to the output end of the programmable power supply through a power supply cable to transmit the temperature and pressure signals of the thermocouple. And the universal meter and the programmable power supply are respectively connected to the computer through communication cables and are connected with the computer to realize data processing. Through the three-in-one design of flexible contact, synchronous sensing and temperature difference control, accurate measurement of the Seebeck coefficient is realized. Through actual measurement, the temperature control precision of the device is + / -0.1 DEG C, the voltage acquisition resolution is 0.1 mu V, and the Seebeck coefficient measurement error is less than 2%.

The invention discloses a preparation method of a Bi2Te3-based thermoelectric material powder metallurgy precursor, which comprises the following steps of: performing hydrogen reduction on a thin strip sample or powder prepared from a zone melting bar of a bismuth telluride-based thermoelectric material at the temperature of 350-400 DEG C to obtain the Bi2Te3-based thermoelectric material powder metallurgy precursor. The Bi2Te3-based thermoelectric material powder metallurgy precursor can be used for preparing a bismuth telluride-based thermoelectric material for eliminating a donor-like effect through a powder metallurgy method. According to the method, powder can be prepared in the air, the donor-like effect generated in the powder preparation process can be eliminated through hydrogen reduction, the process of grinding and powder preparation in a protective atmosphere is avoided, the donor-like effect is eliminated at a lower temperature in a shorter time, the production process of the material can be simplified, the production cost can be saved, and the method is suitable for industrial production. And the optimal carrier concentration can be maintained while grains of the material are refined, and the optimal Seebeck coefficient is obtained.

The application discloses an n-type bismuth telluride-based thermoelectric element NiFeP alloy interface barrier layer and a preparation method thereof, and belongs to the technical field of thermoelectric materials and devices. The barrier layer in the application is an electroplated NiFeP ternary plating layer, the content of Fe is 15-20 wt%, the content of P is 2-4 wt%, the balance is Ni, the thickness is 5-10 microns, and the barrier layer is prepared through substrate pretreatment, electroplating solution preparation, electroplating deposition and post-treatment. The application also constructs a thermoelectric element containing the barrier layer, and the n-type bismuth telluride thermoelectric material layer is connected by a NiFeP alloy interface barrier layer, a SAC305 solder layer and a copper electrode layer in sequence. The barrier layer has excellent diffusion inhibition effect, the interface bonding strength is greater than 16 MPa and the contact resistivity is less than 8 mu omega cm after aging at 200 DEG C for 144 hours. 2 The preparation process is simple, the cost is relatively low, large-scale production is suitable, and the barrier layer is expected to play an important role in the application field of thermoelectric materials and devices.

The invention discloses a method for improving interface bonding strength of a thermoelectric device, which belongs to the technical field of material surface treatment, and comprises the following steps: (1) pretreatment: cutting a bismuth telluride-based thermoelectric material crystal bar into wafers with specified sizes, and then carrying out ultrasonic cleaning by using a cleaning agent; corroding with a corrosive liquid, and ultrasonically cleaning with deionized water; (2) nickel plating: plating a nickel metal layer on the surface of the wafer; (3) tin plating: plating a tin metal layer on the surface of the nickel metal layer; the tin plating process comprises two times, and annealing treatment and strong alkali treatment are sequentially carried out on the wafer between the two times of tin plating. According to the method, the rough surface can be formed on the surface of the wafer by using the corrosive liquid, the interface contact area is increased, and the interface bonding strength is improved; and meanwhile, through two times of tin plating, tin atoms can be uniformly embedded into the nickel metal layer during the second time of tin plating, so that the interface bonding strength is further enhanced.

The invention provides a preparation method of a bismuth telluride-based thermoelectric thin film material, and aims to overcome the defect that most of existing bismuth telluride system materials exist in a rigid form and the application of the bismuth telluride system materials in the emerging fields of wearable equipment, flexible electronic devices and the like is limited. The bismuth telluride material is flexible, the limitation of a traditional thermoelectric material in an application scene is broken through, an innovative thermoelectric management solution is provided for flexible electronic products, and the bismuth telluride material has certain commercial and technical values.

The invention discloses a semiconductor chilling plate welding structure and method, and aims to overcome the defect that the performance of thermoelectric semiconductor particles is degraded due to the fact that soldering tin for assembling a semiconductor chilling plate is likely to overflow from the side edge and make contact with a bismuth telluride material. The thermoelectric module comprises two substrates and a plurality of thermoelectric semiconductor particles arranged between the two substrates, a plurality of copper bonding pads in one-to-one correspondence with the thermoelectric semiconductor particles are preassembled on the opposite surfaces of the two substrates, sunken tin filling grooves are formed in the copper bonding pads, the tin filling grooves are filled with assembling soldering tin, the tin filling grooves are completely covered by the end portions of the thermoelectric semiconductor particles, and the thermoelectric semiconductor particles are arranged on the two substrates. And the assembly soldering tin is welded with the end parts of the thermoelectric semiconductor particles. In the assembling process of the semiconductor chilling plate, soldering tin is not prone to overflowing from the side edge and making contact with the bismuth telluride material, contact reaction is avoided, the reliability of the semiconductor chilling plate is enhanced, and the amount of the soldering tin is well controlled.

The invention discloses a self-energy-supply dustproof lamp for a traffic tunnel and a using method thereof, and relates to the field of lamps, and the key points of the technical scheme are that the self-energy-supply dustproof lamp comprises a self-energy-supply device which is installed at the top end of the lamp and comprises a vibration power generation unit, a temperature difference power generation unit, an energy storage unit and a charging and discharging management unit, the vibration power generation unit is of a combined structure of a piezoelectric ceramic power generation assembly and a spring oscillator, the temperature difference power generation unit is of a combined structure of a bismuth telluride temperature difference power generation piece and a cooling fin, the energy storage unit is a lithium iron phosphate battery, and the charging and discharging management unit integrates an MPPT chip and a protection circuit. The beneficial effects are that the electric energy generated by the two power generation units is transmitted to the charging and discharging management unit, the integrated MPPT chip realizes maximum power point tracking, the electric energy is efficiently adjusted and stored in the energy storage unit formed by the lithium iron phosphate battery, and then the energy storage unit stably supplies power to the lamp. The system can be better adapted to the underground closed / semi-closed traffic tunnel environment with extremely poor illumination conditions.

The invention discloses a front exhaust gradient waste heat power generation system of a new energy hybrid electric vehicle, and relates to the technical field of automobile energy conservation. The system comprises a gradient thermoelectric conversion module, a composite heat dissipation module, an intelligent energy management module and an elastic fixing and sealing module which are arranged in the axial direction of a front exhaust pipe. The gradient thermoelectric module adopts a lead telluride / bismuth telluride dual-material design and is respectively matched with a front exhaust high-temperature area and a front exhaust medium-temperature area; the composite heat dissipation system combines liquid cooling and air cooling to realize temperature difference stable control; the intelligent energy management module is linked with a whole vehicle system through a CAN bus and dynamically distributes electric energy; the elastic fixing mechanism solves the problems of vibration and sealing. The comprehensive conversion efficiency reaches 8%-12%, the fuel economy of the whole vehicle can be improved by 4%-6%, the system is suitable for the frequent start-stop working condition of the hybrid electric vehicle, installation and maintenance are convenient and fast, and the remarkable energy-saving effect and industrialization value are achieved.

The invention relates to the field of thermoelectric technology. In order to solve a series of problems such as the excessively thick Ni layer on the surface of conventional bismuth telluride leading to increased device load, reduced refrigeration temperature difference, complex process, high cost, poor bonding between the Ni layer and bismuth telluride, and insufficient reliability of TEC, the invention proposes a surface treatment technology for bismuth telluride materials. The technology utilizes a composite treatment process of ion implantation and vacuum plating technologies such as multi-arc plating or magnetron sputtering to improve the bonding between the bismuth telluride and the Ni layer, reduce the internal load of TEC, and increase the temperature difference. At the same time, due to the improved bonding between the Ni layer and the bismuth telluride substrate, the reliability of the TEC product is optimized.

The utility model relates to the technical field of CPUs, and discloses a dustproof CPU cooling fan which comprises a cooling shell, the inner bottom wall of the cooling shell is slidably connected with a fixing frame, the inner wall of the fixing frame is fixedly connected with a plurality of graphene cooling fins, the left side of the fixing frame is fixedly connected with a bismuth telluride module, and the right side of the fixing frame is fixedly connected with a plurality of graphene cooling fins. The left side of the bismuth telluride module is fixedly connected with a paraffin plate, the left side of the paraffin plate and the right side of the fixing frame are fixedly connected with the same bidirectional pulsating heat pipe, the rear side of the inner bottom wall of the heat dissipation shell is fixedly connected with a fixing frame, and the top of the fixing frame is fixedly connected with a first servo motor. According to the utility model, the heat of the CPU is transmitted through the paraffin plate, the heat is conducted to the graphene cooling fin through the bidirectional pulsating heat pipe, the first servo motor drives the cooling fan to accelerate the dissipation of the heat on the graphene cooling fin, and meanwhile, part of the heat transmitted by the paraffin plate is converted into electric power through the thermoelectric module and is stored in the storage battery for later use.

This invention discloses a method for separating bismuth from waste bismuth telluride thermoelectric materials, belonging to the field of separation and purification technology. The method utilizes a macroporous, weakly basic styrene-based anion exchange resin containing tertiary amines to adsorb bismuth, followed by stepwise elution of the adsorbed resin with an eluent to separate bismuth from the bismuth telluride leachate, yielding a high-concentration bismuth-containing solution. The method disclosed in this invention features high selectivity, mild reaction conditions, simple operation, good recycling performance, and minimal environmental pollution. It can solve the environmental hazards caused by the accumulation of waste bismuth telluride thermoelectric materials and also realize the recycling of scarce metal resources such as bismuth, antimony, tellurium, and selenium, alleviating resource scarcity.

The invention discloses a two-dimensional bismuth compound / gallium arsenide heterojunction, a preparation method thereof and application of the two-dimensional bismuth compound / gallium arsenide heterojunction in a photoelectric detector, and belongs to the field of semiconductor devices. Two-dimensional bismuth compounds (bismuth selenide or bismuth telluride) are prepared on a cleaned and pre-masked gallium arsenide substrate through an electron beam evaporation method, the two-dimensional bismuth compound / gallium arsenide heterojunction is formed, and the thickness of a two-dimensional bismuth compound film is controllable. And preparing a symmetric or asymmetric electrode by electron beam evaporation to obtain a prototype device of the photoelectric detector. The preparation process is simple, the repeatability is good, the detector can achieve the high detection rate (up to-1014 Jones) of optical signals from the ultraviolet band to the near-infrared band (367-1064 nm) under the room temperature condition and without bias voltage, and meanwhile the excellent cycling stability and air stability are achieved.

The invention belongs to the technical field of thermoelectric materials, and provides a composite P-type bismuth telluride-based material and a preparation method thereof in order to improve the thermoelectric performance of the thermoelectric materials, the composite P-type bismuth telluride-based material comprises a P-type bismuth telluride matrix with the chemical formula being Bi < 0.5 > Sb < 1.5 > Te < 3.2 > and a compound used for compounding, the chemical formula of the composite compound is selected from one or more of Cu2GeSe3, Ag8GeTe6 and Ag5Te3, and the chemical formula of the P-type bismuth telluride matrix is Bi < 0.5 > Sb < 1.5 > Te < 3.2 >. And the usage amount of the composite compound is 0.04-0.1% of the mass of the P-type bismuth telluride matrix. According to the P-type bismuth telluride-based composite material provided by the invention, crystal boundary, second phase and other defects are introduced after compounding to enhance phonon scattering, so that the lattice thermal conductivity is effectively reduced, and finally, the improvement of the material performance is realized by optimizing the carrier concentration and reducing the lattice thermal conductivity.