Influence of Ni on the thermoelectric properties of the partially filled calcium skutterudites CayCo4−xNixSb12

作     者：M. Puyet A. Dauscher B. Lenoir C. Bellouard C. Stiewe E. Müller J. Hejtmanek J. Tobola 

作者机构：Faculty of Physics and Applied Computer Science AGH University of Science and Technology 30-059 Krakow Poland 

出 版 物：《Physical Review B》 (Phys. Rev. B Condens. Matter Mater. Phys.)

年 卷 期：2007年第75卷第24期

页      面：245110-245110页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

摘      要：We have synthesized and studied the structural and thermoelectric properties of Ni-substituted partially filled CayCo4−xNixSb12 (y∼0.10 and 0.18; 0x0.10) skutterudites. Electrical and thermal properties have been measured in a wide range of temperature (2–800K). It was found that the presence of Ni increases drastically the dimensionless figure of merit at moderated temperature with respect to the Ni-free analogous samples. These greater thermoelectric properties are discussed in view of electronic structure features near EF as resulted from KKR-CPA calculations. Both experimental findings and computed DOS characteristics point to the conclusion that another channel of electrical conductivity, related to the presence of d−Ni states and opening additional electron Fermi surface pocket, is presumably responsible for the drop of electrical resistivity with respect to the Ni-free samples. In the same time, important DOS variations near EF were found in CayCo4−xNixSb12, as previously in CayCo4Sb12. This gives rise to a large thermopower detected in the two series of compounds.