Strain-engineered photoelectric conversion properties of lateral monolayer WS2/WSe2 heterojunctions

Abstract In order to explore the strain engineering for the electronic and optoelectronic properties of lateral monolayer heterojunctions, we develop a modified detailed balance method to search for the optimized power conversion efficiency (PCE) based on atomic-bond-relaxation mechanism. We find that the interface band alignment occurs a type II to type I transition at 7.8% tensile strain, and the optimized PCE of WS 2 /WSe 2 lateral heterojunction can be up to ∼4.41%. Our method provides a vital guidance for the design of high-quality solar cell devices composed of a lateral two-dimensional heterostructure.