Improvement of thermoelectric and mechanical properties of BiCuSeO-based materials by SiC nanodispersion

Thermoelectric materials have great application prospects in the fields of micro-refrigeration, waste heat utilization and catalysis, and BiCuSeO is one of the oxide thermoelectric materials with the best comprehensive thermoelectric properties at present. Herein, the dispersion of 20-nm SiC in BiCuSeO matrix has greatly increases the thermoelectric and mechanical properties of the system. SiC nanoparticles dispersed in BiCuSeO matrix can act as energy filters to increase the Seebeck coefficient, on the other hand, as phonon scattering centers to scatter the low- and mid-frequency phonons effectively to reduce the lattice thermal conductivity, combined with point defects such as Pb-Bi(+) scattering the high-frequency phonons, thus achieving the scattering enhancement of full-frequency phonons. In addition, the mechanical strength and machinability of BiCuSeO have been improved significantly due to the dispersion strengthening effect of SiC nanoparticles. (C) 2019 Elsevier B.V. All rights reserved.