B掺杂CoSi的微观组织和单晶热电性能

来源期刊：中国有色金属学报2004年第12期

论文作者：周扬 李成川 任维丽 张澜庭 吴建生

文章页码：2055 - 2059

关键词：B；固溶；晶格常数；CoSi单晶；热电性能

Key words：B; solid solution; lattice parameter; CoSi single crystal; thermoelectric performance

摘    要：研究了掺杂B后CoSi化合物的微观组织及单晶的热电性能。结果表明：B在CoSi中的最大固溶度为0.4%（摩尔分数），CoSi化合物的晶格常数随着B含量的增加线性减小，当B含量达到其最大固溶度时晶格常数不再变化；电弧熔炼制备的CoSi_1-xB_x材料具有很多空洞和裂纹，单晶试样大大减少了组织上的缺陷；掺杂B后CoSi_0.995B_0.005单晶仍为N型传导，Seebeck系数的绝对值增加，电阻率下降，热导率升高；掺杂B后热电优值（ZT）增加。

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 CoSi_1-xB_x 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.

基金信息：国家自然科学基金重点资助项目