Modulation doping of p-type Cu_(12)Sb_(4)S_(13)toward improving thermoelectric performance  

作　　者：Khak Ho Lim Mingquan Li Yu Zhang Yue Wu Qimin Zhou Qingyue Wang Xuan Yang Pingwei Liu Wen-Jun Wang Ka Wai Wong Ka Ming Ng Yu Liu Andreu Cabot 

机构地区：[1]Institute of Zhejiang University-Quzhou,Quzhou 324000,China [2]College of Chemical and Biological Engineering,Zhejiang University,Hangzhou 310007,China [3]School of Chemistry and Chemical Engineering,Hefei University of Technology,Hefei 230009,China [4]Materials Research Institute,The Pennsylvania State University,University Park,PA 16802,USA [5]Ostia Technologies Limited,United Kingdom [6]Department of Chemical and Biological Engineering,The Hong Kong University of Science and Technology,Clear Water Bay,Hong Kong,China [7]ICREA,Pg.Lluis Companys 23,Barcelona 08010,Spain [8]Catalonia Energy Research Institute-IREC,Sant Adria del Besos,Barcelona 08930,Spain

出　　处：《Journal of Materials Science & Technology》2024年第4期71-79,共9页材料科学技术（英文版）

基　　金：Dr.K.H.Lim acknowledges the financial support of the National Natural Science Foundation of China(Grant No.22208293);Research Funds of the Institute of Zhejiang University-Quzhou(Nos.IZQ2021RCZX003,IZQ2021RCZX002,IZQ2021KJ2024,IZQ2022KYZX09);supported by the State Key Laboratory of Fluorinated Greenhouse gases Replacement and Treatment(No.SKLFGGRT2022001);the State Key Laboratory of Electrical Insulation and Power Equipment(No.EIPE23201);Dr.Y.Liu acknowledges funding from the National Natural Science Foundation of China(NSFC)(Grants No.22209034);the Innovation and Entrepreneurship Project of Overseas Returnees in Anhui Province(Grants No.2022LCX002)。

摘　　要：The commercial viability of thermoelectric(TE)devices relies heavily on two factors:cost reduction and efficiency enhancement.In this study,we first produce p-type Cu_(12)Sb_(4)S_(16-x)(x=0,3,4)using a low-temperature bottom-up approach and demonstrate Cu_(12)Sb_(4)S_(13)to show the best TE performance among the three tested compositions.Subsequently,the TE energy conversion efficiency of Cu_(12)Sb_(4)S_(13)is further enhanced by optimizing its electronic band structure through the incorporation of small amounts of tel-lurium.At an optimal Te content of 5 mol%,more than a twofold increase in the TE figure of merit(zT)is obtained.To gain insight into the mechanism of improvement on the transport properties of the mate-rial,we compare the interphase transport mechanism by incorporating nanodomains of different metals(Ag and Cu)into the Cu_(12)Sb_(4)S_(13)matrix.The improved electrical conductivity obtained with Cu_(12)Sb_(4)S_(13)-Te nanocomposites is attributed to a charge flooding of the Cu_(12)Sb_(4)S_(13)surface.In contrast,excessive down-ward band-bending at the interphases of Ag/Cu metal-semiconductor drastically reduces the electrical conductivity.Besides,a weighted mobility(μw)analysis shows a dominant thermal activation of carri-ers in Cu_(12)Sb_(4)S_(13)-Te nanocomposites.In this material,a strong decrease in lattice thermal conductivity is also found,which is associated with a phonon-carrier scattering mechanism.Our work shows the impor-tance of proper band-engineering in TE nanocomposites to decouple electrical and thermal transport to enhance TE performance,and the efficacy ofμw for electrical and thermal transport analysis.

关 键 词：Modulation doping THERMOELECTRIC Interphase transport Charge flooding Phonon-carrier scattering 

分 类 号：TB34[一般工业技术—材料科学与工程]