( 上海交通大學(xué) 材料科學(xué)與工程學(xué)院
教育部高溫材料及測試開放實驗室, 上海 200030)
摘 要: 研究了摻雜B后CoSi化合物的微觀組織及單晶的熱電性能。結(jié)果表明：B在CoSi中的最大固溶度為0.4%（摩爾分?jǐn)?shù)），CoSi化合物的晶格常數(shù)隨著B含量的增加線性減小，當(dāng)B含量達到其最大固溶度時晶格常數(shù)不再變化；電弧熔煉制備的CoSi1-xBx材料具有很多空洞和裂紋，單晶試樣大大減少了組織上的缺陷；摻雜B后CoSi0.995B0.005單晶仍為N型傳導(dǎo)，Seebeck系數(shù)的絕對值增加，電阻率下降，熱導(dǎo)率升高；摻雜B后熱電優(yōu)值（ZT）增加。
關(guān)鍵字: B；固溶；晶格常數(shù)；CoSi單晶；熱電性能
of B-doped CoSi
ZHANG Lan-ting, WU Jian-sheng
（ Key Laboratory of Ministry of Education for High Temperature Materials
and Testing, School of Materials Science and Engineering,
Shanghai Jiaotong University, Shanghai 200030, China）
Abstract: The microstructure and thermoelectric performance of B-doped binary compound cobalt monosilica were investigated. The results show that the solid solubility limit of B in CoSi is 0.4%(molar fraction). With the increase of the composition of B, the lattice parameter of CoSi linearly reduces and reaches a constant value when the content of B exceeds its solubility limit. There are lots of pores and flaws in CoSi1-xBx compounds prepared by arc melting, while defects in single crystal specimens are greatly reduced. B-doped CoSi single crystal shows N-type conduction. The substitution of B onto the Si sites causes an increase in the absolute value of Seebeck coefficient and the thermal conductivity, while the electrical resistivity decrease. The figure of merit (ZT) of B-doped CoSi single crystal slightly increases.
Key words: B; solid solution; lattice parameter; CoSi single crystal; thermoelectric performance
