Simultaneous regulation of electrical and thermal transport properties in CuInTe2 by directly incorporating excess ZnX (X=S, Se)

Abstract Developing high thermoelectric performance CuInTe 2 based materials is technologically and environmentally intriguing, in order to achieve this, nanoscale heterostructure barrier blocking is proposed and adopted in this work by directly incorporating excess ZnX (X=S, Se) to regulate the electrical and thermal transport properties of CuInTe 2 . The results prove that part of the ZnX dissolves into the CuInTe 2 matrix during the hot press process while the residual ZnX acts as a nanoscale heterostructure barrier blocking for both the hole and phonon. As a consequence, three thermoelectric parameters of the CuInTe 2 have been optimized simultaneously by this approach, owing to the formation of Zn- In point defects to improve carrier concentration, the concurrent hindering to the minority carriers resulting from the energy level difference between matrix and nano-heterostructure to enhance the Seebeck coefficient, and intensive phonon scattering by the nanoscale heterostructure barrier blocking to reduce the thermal conductivity. Eventually, a 90% enhanced ZT value of 1.52 has been obtained in the 6 wt% ZnS added CuInTe 2 sample.