Thermoelectric properties of correlated electron systems Ln 3Pt4Ge6and LnPt4Ge12(Ln = Ce, Pr) and non-centrosymmetric X 2 T 12P7(X = Yb, Hf and T = Fe, Co)

Abstract

We report measurements of the thermoelectric power Sand electrical resistivity ρ for correlated electron systems Ln 3Pt 4Ge6and LnPt4Ge12(Ln= Ce, Pr) and X 2 T 12P7(X= Yb, Hf and T= Fe, Co). The thermoelectric power factor S 2/ ρ is utilized as a means to assess the potential viability of these materials for thermoelectric applications. Sis observed to be sensitive to Lnin Ln 3Pt 4Ge6and LnPt4Ge12with Ce-based compounds providing a much larger Sand S 2/ ρ than Pr-based materials. The character of Sfor the Ce-based compounds is consistent with an intermediate Ce valence. In the case of X 2 T 12P 7compounds reported herein, it appears that it is possible to tune the magnitude of Smore effectively by varying Trather than X; the magnitude of Sis significantly larger with T= Fe than when T= Co. © 2013 Springer Science+Business Media Dordrecht.