Solid solution Pb1−xEuxTe: constitution and thermoelectric behavior

Abstract

Polycrystalline samples of the solid solution Pb_1−xEu_xTe were prepared by the spark-plasma technique. In contrast to the literature data, the homogeneity range of the solid solution amounts only to 0 ≤ x ≤ 0.02 under the selected preparation conditions. The implementation of Eu into the PbTe lattice was monitored by refinement of the lattice parameters. The thermoelectric properties of the prepared materials were investigated above room temperature. In samples with compositions x ≤ 0.04, the solid solution Pb_1−xEu_xTe reveals a metal–semiconductor transition around 500 K going in parallel to the p–n transition in the conductivity. No significant influence of the europium substitution on the thermoelectric figure-of-merit was observed in stoichiometric bulk materials.

Collaboration between Prof. Yuri Grin's group at Max-Planck Institute of Chemical Physics of Solids and Prof. Jing-Tai Zhao's group at Shanghai University (at Shanghai Institute of Ceramics, Chinese Academy of Sciences before 2014) in the field of Solid State Chemistry and Physics of intermetallic compounds started from 1999 followed by an establishment of a Partner Group between the Max-Planck Society and Chinese Academy of Sciences. The collaboration is highly recognized, in particular the studies on exploration of novel high-performance thermoelectric materials – so-called “122” Zintl phases – in pnictide systems and germanium clathrates. The long-term collaboration generated more than 30 joint publications in international journals and many presentations at national and international conferences, more than 10 co-supervised students and postdocs, and a series of workshops on X-ray Crystallography in Shanghai and Dresden.