Enhanced thermoelectric performance of orientated and defected SnTe

Enhancing the thermoelectric performance of SnTe lies in the core of research, which has inspired effective and novel approaches such as point defects, electronic band structure engineering and nano-structuring. Herein, we propose an alternative route to enhance the thermoelectric performance of SnTe through a "top-down" hot deformation (HD) process. The HD induces a special orientation in the rock-salt SnTe, which is exclusive to layered structure materials and seldom achieved in cubic structure materials. In addition, the HD creates high density lattice defects such as dislocations and strain fluctuations in SnTe, a highly desired microstructure feature for low lattice thermal conductivity. As a result, the HD enables similar to 45% and similar to 58% enhancement in the maximum figure of merit ZT along the in-plane and cross-plane directions of SnTe. Such significant enhancement indicates great potential for the HD in enhancing the ZT of SnTe, which is extendable to other thermoelectric materials. (C) 2020 Elsevier B.V. All rights reserved.