Predicting two-dimensional diphosphorus silicide monolayer by the global optimization method

Abstract

Using CALYPSO methodology, we proposed a stable two-dimensional P2Si monolayer, as examined via cohesive energy, mechanical criteria and all positive phonon spectra. The P2Si monolayer is an indirect semiconductor with large band-gap of 1.6055 (2.019) eV using PBE (HSE06) hybrid functional. Moreover, it possesses better carrier mobilities and a ultra-high optical absorption capacity in visible region. Furthermore, the effects of strains on band structure have been studied, and a semiconductor-to-metal transition exists for −10% strain ratio case. These theoretical findings endow the P2Si Monolayer to be a 2D material holding great promises for applications in high-performance electronics and optoelectronics.