Room-Temperature Thermoelectric Conversion by Dipole-Enhanced Rashba Spin-Orbit Coupling

Abstract

Summary The development of the Internet of Things requires devices that are light, wireless, and wearable. With no cable for power and limited space for a battery, powering these devices becomes a daunting challenge. Wearable devices that are self-powered through harvesting heat from surroundings may address this challenge; however, conventional thermoelectric materials suffer either from poor mechanical stability or low room-temperature conversion efficiency. Based on density functional theory and Boltzmann transport calculations, we propose that monolayer WSTe promises a wearable thermoelectric material that exploits the synergic effects between the Rashba-type spin-orbit coupling and out-of-plane electric dipole. The maximum calculated room-temperature ZT value reaches 0.41, which is among the best 2D wearable thermoelectrics. Moreover, monolayer WSTe should possess an in-plane stiffness of ∼100 N/m and a fracture point up to 25%. Our study may shed light on the synergistic effects of electric dipole and Rashba spin-splitting on thermoelectric conversion for wearable electronics.