Optimal performance of Cu_(1.8)S_(1-x)Te_(x) thermoelectric materials fabricated via high-pressure process at room temperature

作     者：Rui ZHANG Jun PEI Zhi-Jia HAN Yin WU Zhao ZHAO Bo-Ping ZHANG 

作者机构：Beijing Municipal Key Laboratory of New Energy Materials and TechnologiesSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China 

出 版 物：《Journal of Advanced Ceramics》 (先进陶瓷（英文）)

年 卷 期：2020年第9卷第5期

页      面：535-543页

核心收录：

学科分类：08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：supported by the National Key R&D Program of China(Grant No.2018YFB0703600) the National Natural Science Foundation of China(Grant No.11474176) 

主　　题：Cu_(1.8)S Te doping nanostructure high pressure thermoelectric(TE) 

摘      要：Cu_(1.8)S has been considered as a potential thermoelectric(TE)material for its stable electrical and thermal properties,environmental benignity,and low ***,the TE properties of nanostructured Cu_(1.8)S_(1-x)Te_(x)(0≤x≤0.2)bulks fabricated by a facile process combining mechanical alloying(MA)and room-temperature high-pressure sintering(RT-HPS)technique were optimized via eliminating the volatilization of S element and suppressing grain ***,a single phase of Cu_(1.8)S was obtained at x=0,and a second Cu_(1.96)S phase formed in all Cu_(1.8)S_(1-x)Te_(x) samples when 0.05≤x≤*** further increasing x to 0.15≤x≤0.2,the Cu_(2-z)Te phase was detected and the samples consisted of Cu_(1.8)S,Cu_(1.96)S,and Cu_(2-z)Te *** from a modified band structure and the coexisted phases of Cu_(1.96)S and Cu_(2-z)Te,the power factor is enhanced in all Cu_(1.8)S_(1-x)Te_(x)(0.05≤x≤0.2)*** with a drastic decrease in the thermal conductivity due to the strengthened phonon scatterings from multiscale defects introduced by Te doping and nano-grain boundaries,a maximum figure of merit(ZT)of 0.352 is reached at 623 K for Cu_(1.8)S_(0.875)Te_(0.125),which is 171%higher than that of Cu_(1.8)S(0.130).The study demonstrates that doping Te is an effective strategy to improve the TE performance of Cu_(1.8)S based materials and the proposed facile method combing MA and RT-HPS is a potential way to fabricate nanostructured bulks.