High-performance copper selenide nanocomposites for power generation.

Cu 1.97 Se- x wt. % In 2 O 3 (x = 0–1) bulk composites are fabricated by combining high-temperature melting and spark plasma sintering technology. The doping of In3+in Cu vacancies tunes the carrier concentration and modifies the band structure of Cu 1.97 Se. Additionally, excessive In 2 O 3 particles benefit the construction of multiple lattice defects to strengthen phonon scattering and suppress the long-range migration of Cu ions, resulting in obviously reduced thermal conductivity and improved service stability. Ultimately, a peak ZT value of 1.43 is obtained at 873 K for the Cu 1.97 Se-0.5 wt. % In 2 O 3 bulk specimen, which is almost 150% higher than that of pristine sample. The thermoelectric conversion efficiency and mechanical properties of the composites sample are also measured. The results suggest that Cu 1.97 Se-based nanocomposites offer potential for use in power generation device assembly. [ABSTRACT FROM AUTHOR]