Thermoelectric properties of two-dimensional hexagonal indium-VA

The electrical properties and thermoelectric (TE) properties of monolayer In-VA are investigated theoretically by combining first-principles method with Boltzmann transport theory. The ultralow intrinsic thermal conductivities of 2.64 W·m^-1·K^-1 (InP), 1.31 W·m^-1·K^-1 (InAs), 0.87 W·m^-1·K^-1 (InSb), and 0.62 W·m^-1 K^-1 (InBi) evaluated at room temperature are close to typical thermal conductivity values of good TE materials (κ < 2 W·m^-1·K^-1). The maximal ZT values of 0.779, 0.583, 0.696, 0.727, and 0.373 for InN, InP, InAs, InSb, and InBi at p-type level are calculated at 900 K, which makes In-VA potential TE material working at medium-high temperature.