Enhanced photocatalytic properties of s-triazine-based-g-C3N4/BlueP and g-C3N4/G/BlueP vdW heterostructures: A DFT study

Constructing a Z-scheme heterostructure from selected semiconductors has been proved to be an effective route for attaining the strong redox capability and broad light absorption range simultaneously. In this work, we investigated the electronic, optical and photocatalytic properties of g-C3N4/BlueP and g-C3N4/G/BlueP van der waals heterostructures (vdWHs) by density functional theory (DFT) calculations. The staggered band alignment and the interfacial built-in electric field originated from the charge transfer from g-C3N4 to BlueP depict the Z-scheme photocatalytic mechanism of the g-C3N4/BlueP vdWH. Meanwhile, the vdWH shows an enhanced absorbance at the ultraviolet and visible light range compared to the individual g-C3N4 and BlueP monolayers. Furthermore, the intercalation of Graphene monolayer between g-C3N4 and BlueP is proved to modulate the interfacial built-in electric field, while retaining the staggered band alignment simultaneously. The significant enhancement of the visible light region absorption efficiency promoted by the gap-state of intercalated Graphene manifests the co-catalytic effect of Graphene and the applicable prospect of the constructed ternary heterostructure in photocatalysis area.