LAUSR

Abstract Digenite (Cu1.8S) as a low-cost, low-toxicity thermoelectric material attracts more and more attention due to its excellent electrical transport. In this paper, the Bi2S3 and Bi2S3@Bi core-shell were introduced to Cu1.8S bulk prepared by mechanical alloying (MA) and spark plasma sintering (SPS) technique. The core-shell structural nanorods were synthesized by a hydrothermal method using Bi2S3 nanorods as the template. The effects of adding Bi2S3 on the thermoelectric properties of Cu1.8S were investigated in detail at the temperature between 323 K and 723 K. The power factor of Cu1.8S was enhanced by introducing Bi2S3@Bi core-shell nanorods due to improved Seebeck coefficient. A maximum thermoelectric figure of merit (ZT) value of 0.77 was attained at 723 K due to optimized thermal transport properties and to the maintained electrical transport properties, which is 2.4 times higher than that of the pristine Cu1.8S (0.32 at 723 K).