Maximizing Thermoelectric Figures of Merit by Uniaxially Straining Indium Selenide

Abstract

A majority of the electricity currently generated is regrettably lost as heat. Engineering high-efficiency thermoelectric materials which can convert waste heat back into electricity is therefore vital for reducing our energy fingerprint. ZT, a dimensionless figure of merit, acts as a beacon of promising thermoelectric materials. However, engineering materials with large ZT values is practically challenging, since maximizing ZT requires optimizing many interdependent material properties. Motivated by recent studies on bulk indium selenide that suggest it may have favorable thermoelectric properties, here we present the thermoelectric properties of monolayer indium selenide in the presence of uniaxial strain using first-principles calculations conjoined with semiclassical Boltzmann transport theory. Our calculations indicate that conduction band convergence occurs at a compressive strain of −6% along the zigzag direction and results in an enhancement of ZT for p-type indium selenide at room temperature. Fu...