Tunable Electronic Property and Robust Type-II Feature in Blue Phosphorene/MoSi2N4 Bilayer Heterostructure

Constructing novel van der Waals heterostructures (vdWHs) is one of the effective methods for expanding the properties and applications of single materials. In this contribution, a blue phosphorene (Blue P)/MoSi2N4 vertical bilayer vdWH was constructed, and its crystal and electronic structures as well as optical properties were systematically studied via first principles calculation. It was found that the Blue P/MoSi2N4 vdWH with good thermal and dynamic stabilities belongs to the type-II indirect bandgap semiconductor with the bandgap of 1.92 eV, which can efficiently separate electrons and holes. Additionally, the two band edges straddle the redox potential of water, and the charge transfer follows the Z-scheme mode, making the Blue P/MoSi2N4 vdWH a promising catalyst of hydrogen production through splitting water. Meanwhile, the Blue P/MoSi2N4 vdWH has higher optical absorption than its two component monolayers. Both the external electric field and vertical strain can easily tailor the bandgap of Blue P/MoSi2N4 vdWH while still preserving its type-II heterostructure characteristics. Our proposed Blue P/MoSi2N4 vdWH is a promising photovoltaic two-dimensional material, and our findings provided theoretical support for the related experimental exploration.