High thermoelectric and mechanical performance in highly dense Cu2−xS bulks prepared by a melt-solidification technique

Highly dense Cu2−xS bulks, fabricated by a melt-solidification technique, show high thermoelectric performance with zT of approx. 1.9 at 970 K. The Cu2−xS bulks show good thermal heat flow and diffusivity stability, and they exhibit excellent mechanical properties, with hardness of approx. 1 GPa. Density functional theory calculations indicate that Cu2−xS is an intrinsic p-type conductor.