Ultra-low thermal conductivity and high thermoelectric performance realized in a Cu3SbSe4 based system

摘要

Cu3SbSe4-Based materials were fabricated through Sn-doping and AgSb_(0.98)Ge_(0.02)Se2 incorporation and their thermoelectric properties were investigated in the temperature range from 300 K to 675 K. A remarkable enhancement in thermoelectric performance was obtained, which can be ascribed to the synergistic adjustment of electrical and thermal transport. The introduction of AgSb_(0.98)Ge_(0.02)Se2 nanoparticles strengthened phonon scattering in the composites, resulting in a low thermal conductivity. Simultaneously, a high power factor was maintained. As a result, a maximum figure of merit of 1.23 was obtained at 675 K for the sample Cu3Sb_(0.96)Ge_(0.04)Se4–3 wt% AgSb_(0.98)Ge_(0.02)Se2, which is one of the highest values ever reported in the Cu3SbSe4-based system.