Passivated B-O, B-S codoping to improve the photocatalytic efficiency in C2N monolayer: First-principles study

Abstract

In this paper, we explored systematically the effects of non-metal elements (B, O, and S) monodoping and passivated codoping of B-S and B-O in C2N monolayer. The band structure, band edge position and charge density distribution of doped-C2N are investigated. Our results show that the monodoping of B, O, S introduce flat impurity bands around the Fermi level. The passivated codoping of B-O or B-S can effectively decrease the bandgap, and the band edge position is more favorable for water splitting compared with that of C2N monolayer. A large dispersion of conduction and valance band can be observed for B-S or B-O codoping, which is beneficial for the carriers' mobility. Moreover, the separation of electron and hole density to extend after doping can decrease the combination rate in photocatalytic. Our results predict that passivated B-S or B-O doped C2N are promising water-splitting photocatalyst.