Antimony tellurides are used for the production of high-purity semiconductors
Publish Time: 2022-08-08 Origin: Site
Sb2Te3 is a main material with basic functions, and its thermoelectricity is applied as a new energy source such as solar energy on the basis of doping properties and solid-state phase transition properties are used as key materials for publicity. Among them, the next generation based on CMOS (Complementary Metal Oxide Semiconductor) technology needs to find more suitable materials in the context of GeTeSb2Te3 system.
The thermodynamically stable phase of Sb2Te3 is a hexagonal beam structure with a group space of 166 (R-32/m) a = 0∙43nmc = 3∙04nm. Amorphous and face-centered cubic metastable phases transform to low-energy thermal hexagonal phases under electron beam irradiation.
The properties of antimony telluride
Paradigm semiconductors for elements in groups V, VI of the periodic table. Covalent, ionic bond, there is a certain De Waals surface bond components, triangular crystal system, the original cell is a rhombic hexamer.
Melting point: 629 °C
Relative density: 6.5018g/cm3
Molecular weight: 626.30
Stability: Stable. No
Solubility: insoluble
Properties: Gray lump.
Solubility: Insoluble in water.
Dangerous Goods Transport Number: UN 1549 6.1/PG 3
Antimony telluride powder preparation
Antimony telluride is prepared by passing hydrogen telluride into an acid solution of antimony (III) chloride or heating a mixture of elemental tellurium and antimony.
Taking SbCl3 and K2TeO3 as starting materials, according to the stoichiometric ratio of n(SbCl3): n(K2TeO3)=2:3, weigh 0.002mol of SbCl3 and 0.003mol of K2TeO3, and add them to a 250-ml two-necked round-bottomed flask, Then add 0.5g polyvinylpyrrolidone, 0.5g NaOH and 80 ml of diethylene glycol (measured with a measuring cylinder), place the two-necked round-bottomed flasks in a temperature-controlled heating mantle, set the temperature to 240 ° C, keep the temperature for 4 h, adjust Speed 500r/min. When the temperature of the reactant drops to room temperature, it is transferred to a 100 ml centrifuge tube, and centrifuged three times with isopropanol and acetone respectively. The speed of the centrifuge is set to 4000 r/min for 4 min. The black precipitation is taken out and placed in an oven at 70 ° C and dried for 6h, finally obtains black Sb Te Nano powder.
Antimony telluride pieces application
1) Mainly used for semiconductors, optoelectronic devices and thermoelectric semiconductor refrigeration, thermoelectric power generation, etc.
2) Antimony telluride is used for preparing an antimony telluride/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate thermoelectric composite material, which belongs to the field of thermoelectric composite material synthesis. The preparation method is as follows: 1) preparing antimony telluride nano-powder; 2) performing plasma discharge sintering on the antimony telluride nano-powder prepared in step 1) under vacuum conditions, and cooling to obtain Sb2Te3 bulk material; 2) The prepared Sb2Te3 bulk material was cut, and then immersed in poly(3,4-ethylenedioxythiophene): polystyrene sulfonate solution, and stored at 3°C--5°C for 20-40 In the next day, antimony telluride/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate thermoelectric composites were obtained. The advantages are: the process has low energy consumption, low cost and simple process; the composite material of the invention has excellent thermoelectric performance and high ZT value.
3) Preparation of high thermoelectric antimony telluride micro-nanocrystals and their bulk materials: Dissolve antimony precursor in polyol, then mix the aforementioned solution with tellurium precursor and complexing agent, heat and stir at 140~180℃ After cooling to 100~120℃, adding a reducing agent, react at 120~180℃ for 6~48h to obtain a precipitate, then wash with absolute ethanol until the cleaning solution is neutral, and vacuum dry the washed precipitate to obtain antimony telluride Micro-nanocrystals, the obtained antimony telluride micro-nanocrystals are cold-pressed into flakes and then annealed in a mixed gas with a volume ratio of Ar and H2 of 92%: 8% at 300~400 °C for 2~24h to obtain antimony telluride bulk. The obtained antimony telluride micro-nanocrystals and their bulk materials have the characteristics of high purity, good thermoelectric performance, and the preparation method is simple, low in cost, easy to repeat, suitable for mass production, and very promising for commercialization.
4) A topological insulator material is prepared, which belongs to the field of preparation of new materials. The insulator material is an antimony telluride/tellurium segmented nanowire array or a tellurium nanodisc array. The invention adopts a template-assisted method to directly obtain regular antimony telluride/tellurium segmented nanowire arrays or tellurium nanodisc arrays on the template, and the prepared nanomaterials are used to regulate the topological insulation properties of the materials. Compared with the preparation of traditional bismuth selenide material, the invention has the characteristics of simple process, low cost, one-time molding and the like.
5) Antimony telluride-based thin film materials are thermoelectric materials with good performance and have been widely studied. Thermoelectric materials are materials that realize the direct conversion of thermal energy and electrical energy, and have important application value and broad application prospects in the fields of thermoelectric power generation and thermoelectric refrigeration. Sb_2Te_3-based compounds are one of the best thermoelectric materials at room temperature. After decades of research, the thermoelectric figure of merit of bulk Sb_2Te_3-based materials has been hovering around 1 at room temperature. With the development of nanotechnology, the nanometerization of thermoelectric materials can increase the scattering of carriers and phonons, so that the thermal conductivity of the material decreases more significantly than the electrical conductivity, which is beneficial to improve the thermoelectric properties of the material.