Significant enhancement of the thermoelectric performance of phosphorene through the application of tensile strain

Abstract

First-principles calculations based on density functional theory showed that the thermoelectric performance of single-atomic-layer phosphorus, referred to as phosphorene, is significantly enhanced by the application of tensile strain along a particular direction. Phosphorene subjected to a 10% strain exhibits a very large power factor exceeding 10 mW/(m·K2), which is almost two orders of magnitude greater than the power factors of conventional flexible thermoelectric materials. This extreme enhancement of the thermoelectric performance is explained by the new concept of a strain-induced energy valley.