Nickel-substituted skutterudites: synthesis, structural and electrical properties

Based on AB(3) (A=Co, Lr, Rh and B=P, As and Sb) compounds, filled skutteru dites (MA(4)B(12); M=rare earth) are promising new thermoelectric elements, increasing their figure of merit requires realizing substitutions to give these compounds semiconducting character with a carrier concentration aroun d 10(19) cm(-3) and decreasing their thermal conductivity. In this framewor k, many published works have been devoted to CeFe4Sb12 which, although meta llic due to the trivalent character of the cerium ion, is the starting comp ound for numerous substitutions. For CeyFe4-xNixSb12, the substitution of n ickel for iron gives semiconducting compounds. In this paper, we present ou r results on these compounds synthesized by the thermal treatment usually a pplied to obtain CeFe4Sb12. (C) 1999 Elsevier Science S.A. All rights reser ved.