不同Zn含量的GaSb热电半导体及其性能

摘要

采用放电等离子烧结法(SPS)制备了四种不同Zn含量的GaSb热电半导体(分别是GaSb,Zn0.9 Ga 2.1Sb2,ZnGa2Sb2和Zn1.1Ga1.9 Sb2),并分析研究其热电性能.结果表明:加Zn后虽然GaSb的Seebeck系数大幅度降低,但电导率提高了约两个数量级,热导率也得以降低,最终热电性能明显提高.在713K时Zn1.1Ga1.9Sb2的最大ZT值达到0.11,比本征GaSb的ZT值提高了近6倍.%Four GaSb based compounds with A Ⅲ B V type semiconductors (GaSb, Zn0.9Ga2.1Sb2,ZnGa2Sb2 and Zn1.1Ga1.9Sb2 ) were prepared by spark plasma sintering, and their thermoelectric (TE) properties were evaluated. Measurements reveal that although the Seebeck coefficient decreases substantially,thermal conductivity decreases and the electrical conductivity is about two orders high in magnitude compared with that of intrinsic GaSb over the entire temperature range. As a consequence, the thermoelectric performance has been significantly improved. The maximum dimensionless TE figure of merit (ZT) of 0. 11 was achieved for Zn1.1Ga1.9Sb2 at 713 K, which is about 6 times of that of GaSb at the corresponding temperature.