Defects engineering driven high power factor of ZrNiSn-based Half-Heusler thermoelectric materials

The electrical transport properties of ZrNiSn-based Half-Heusler (HH) thermoelectric materials are worth to draw researchers' attention, because it is thought to have no explicit upper limit for improving power factor (PF), leaving great potential to increase figure of merit (ZT). Herein, we conducted defects engineering to control the intrinsic interstitial defect and Ni/vacancy anti-site defect, achieving much improved carrier mobility due to the successful elimination of the electrical potential field perturbation. Ultimately, improvement of PF (similar to 23%) and ZT (similar to 18%) were obtained. Point defects engineering, a useful way to manipulate the electrical properties, can also be extended to other thermoelectric systems.