Enhancing electronic and optical properties of monolayer MoSe2via a MoSe2/blue phosphorene heterobilayer

Abstract

Type-II heterostructures are appealing for application in optoelectronics due to their effective separation of photogenerated charge carriers. Based on density functional and many-body perturbation theories, we investigate the MoSe₂/blue phosphorene (MoSe₂/Blue-P) heterobilayer with three representative stacking configurations. Our calculations indicate that the AA-stacking structure has more thermodynamic and dynamic stability. And it possesses a type-II band alignment with significant band offsets. The band offsets together with an interlayer polarized field will efficiently separate the photogenerated holes and electrons. More interestingly, compared with the MoSe₂ monolayer, the MoSe₂/Blue-P heterobilayer exhibits a significant enhancement of optical absorption in the range of near-ultraviolet and visible light. Also, the observed interlayer exciton has an impressive binding energy (∼670 meV), suggesting that the radiative recombination can be suppressed by the formation of an interlayer exciton. The predicted maximum energy conversion efficiency of MoSe₂/Blue-P can achieve a value as large as 14.3%. These prominent electronic and optical properties provide the MoSe₂/Blue-P heterobilayer with great potential in optoelectronics.