文献类型：会议论文

英文题名：Superstructure and physical properties of skutterudite-related phase CoGe1.5Se1.5

作者：Liang, Y.[1];Fang, B.[1];Zhu, X. M.[1];Liang, M. M.[1]

机构：[1]East China Univ Sci & Technol, Inst Nucl Technol & Applicat, Sch Sci, Meilong Rd 130, Shanghai 200237, Peoples R China

会议论文集：17th IUMRS International Conference in Asia (IUMRS-ICA)

会议日期：OCT 20-24, 2016

会议地点：Qingdao, PEOPLES R CHINA

语种：英文

外文关键词：related skutterudite; CoGe1.5Se1.5; superstructure; electrical resistivity

摘要：CoGe1.5Se1.5 skutterudite-related phase with a homogeneity range has been synthesized by solid-state reaction. The phase purity, homogeneity range, crystal structure, thermal stability and electrical resistivity were studied. XRD data indicates that CoGe1.5Se1.5 crystallized in a modification of the skutterudite CoAs3 type structure with space group R (3) over bar (a = b = 11.751(1) angstrom, c = 14.36(1) angstrom). HRTEM-SAED shows more information about the superstructure to confirm the rhombohedral symmetry with space group R (3) over bar. The lattice parameter of this skutterudite-related phase was found to be dependent on the concentration of Ge and Se. CoGe1.5Se1.5 decomposed between 1073 K and 1173 K under argon atmosphere investigated by in-situ XRD, suggesting a good thermal stability. CoGe1.49Se1.42, CoGe1.43Se1.34 and CoGe1.50Se1.15 dense bulk samples were obtained by hot-press technique. The chemical composition detected by FESEM/EDS suggests the homogeneity range and the existence of voids at framework positions. The electrical resistivity of the compounds decreases with increasing temperature, acting as a semiconductor. The chemical composition has a big influence on the value of electrical resistivity and energy gap.