Van der Waals heterostructures of blue phosphorene and scandium-based MXenes monolayers

Stacked layers in the form of van der Waals (vdW) heterostructures can significantly extend the applications of its building materials. In this study, based on hybrid functional (HSE06) with vdW corrections, we systematically investigated the electronic structure and optical properties of BlueP/Sc2CX2 (X=O,F,OH) vdW heterostructures and their corresponding monolayers. All three heterostructures are indirect bandgap semiconductors with type-II band alignment. The calculated bandgap of BlueP/Sc2CF2 is found to be 1.528 eV. A small amount of charge transfers from BlueP to Sc2CF2 and from Sc2CO2 [Sc2C(OH)2] to BlueP, rendering it p- and n-doped, respectively. The formation of heterostructures enhanced the optical absorption in the visible light region as compared to their parent monolayer, particularly in BlueP/Sc2CF2 and BlueP/Sc2C(OH)2. Heterostructures show excellent device absorption efficiencies (70%–80%) from infrared to ultraviolet spectrum of light. These results suggest that BlueP/Sc2CX2 heterostructures are potential for nanoelectronics, optoelectronics, and photovoltaic device applications.