Copper telluride with manipulated carrier concentrations for high-performance solid-state thermoelectrics

Abstract

• Graphene incorporated Cu 2 Te composites are systematically and carefully fabricated. • Graphene effectively suppresses the carrier concentrations of the Cu 2 Te. • Reduced carrier concentration leads to an enhanced thermoelectric performance. • Substantial ZT of ∼1.47 at 1000 K is achieved, 268% higher than the pristine Cu 2 Te. This study proposed a strategy for effectively diminishing the carrier concentration in Cu 2 Te by introducing graphene sheets. Based on thermoelectric property measurements and single parabolic band modeling, the incorporated graphene effectively reduced the carrier concentration, not only enhancing the thermoelectric performance of the Cu 2 Te/graphene composite but also substantially improving its figure of merit up to ∼1.47 at 1000 K, which is 268% higher than that of pristine Cu 2 Te. This study gives an insight into the control of carrier concentration and thermoelectric properties in Cu 2 Te, and it could be extended to other copper chalcogenides for excellent thermoelectrics.