Enhanced thermoelectric performance of CoSbS_(0.85)Se_(0.15) by point defect

摘要

In this study, we report the effect of Zn doping on the thermoelectric properties of Co_(1-x)Zn_xSbS_(0.85)Se_(0.15)solid solutions(x = 0, 0.02, 0.05, 0.08). The results show the dimensionless figure of merit(zT) increases from 0.17 to 0.34 at 875 K for Co_(0.95)Zn_(0.05)SbS_(0.85)Se_(0.15) sample, due to the noticeable decrease in the lattice thermal conductivity by introducing point defect, which is further confirmed by an analysis based on the Debye-CallawayKlemens model. Meanwhile, the thermoelectric power factor is maintained at high temperatures. This work highlights the important role of point defect in improving the thermoelectric performance of CoSbS-based compounds.