The Frist Theoretical Stydy On The Thermoelectric Properties Of Medium And High Temperature Thermoelectric Materials

With the reduction of non-recyclable energy reserves,the research and development of new types of renewable energy is an important topic of concern to countries around the world at this time.Recently,thermoelectric materials have attracted attention because of their recyclable and pollution-free characteristics.There are promising methods.This paper studies the electronic and thermoelectric properties of medium-and high-temperature materials,and the effect of doping on their thermoelectric properties.Half-Heusler compounds with high thermoelectric properties and low-cost and environmentally friendly ingredients have attracted much attention due to their high electrical conductivity and Seebeck coefficient.And in recent years,it has been discovered that the ternary chalcopyrite semiconductor ?-?-?2(?=Ag,Cu;?=Al,Ga,In;?=S,Se,Te)is a potential high-performance thermoelectric material.The conclusions are as follows:1.In this work,we focused on the effect of Zr partial substitution of Ti on the TiPdSn-based compounds to improve the thermoelectric properties.Based on first-principles and semi-classical Boltzmann transport theory,the structure,electronic properties,and thermoelectric properties of Ti1-xZrxPdSn(X=0,0.25,0.5,0.75,1)were studied to find excellent functional materials.Ti1-xZrxPdSn was found to be a narrow gap direct semiconductor.The maximum predicted ZT value of p-type Ti1-xZrxPdSn at 1100K is 2.43,which indicates that p-type Til-xZrxPdSn semiconductor has potential application prospects in the future.2.This paper takes CuInTe2 as the research object and systematically studies its electronic structure characteristics and related thermoelectric properties.And through the different proportions of doping Al,Ga two elements to study its thermoelectric properties.The the thermoelectric figure of merit of CuIn0.25Al0.25Ga0.5Te2 can reach 2.1 at 800 K,which is significantly better than the previously reported CuInTe2 material.Therefore,our results show that the compound based on CuInTe2 is a promising thermoelectric material,and its thermoelectric properties can be effectively improved by doping.