Melt spinning synthesis of p-type skutterudites : drastically speed up the process of high performance thermoelectrics

Abstract

In this study, via a home-made induction melting process combined with spark plasma sintering technique, we successfully synthesize the nanostructured skutterudites NdxYbyFe3CoSb12 (x + y = 1.0, x = 0.3, 0.4, 0.5, 0.6, 0.7) in less than 3 h, which is significantly faster than that of the solid state reaction (168 h) and the traditional melt spinning method (40 h). Systematical microstructures analysis of the sintered bulk materials reveals the largely refined matrix grains (100-300 nm) and ubiquitous YbSb precipitates (~ 30 nm), resulting in a very low lattice thermal conductivity. A peak ZT up to 1.02 at 760 K is obtained for Nd0.6Yb0.4Fe3CoSb12 compound.