Arsenene-Based Heterostructures: Highly Efficient Bifunctional Materials for Photovoltaics and Photocatalytics.

Constructing suitable type II heterostructures is a reliable solution for high-efficient photovoltaic and photocatalytic materials. Arsenene, as a rising member of monoelemental two-dimensional materials, shows great potential as a building block of heterostructures because of its suitable band gap, high carrier mobility, and good optical properties. On the basis of accurate band structure calculations by combining the many-body perturbation GW method with an extrapolation technique, we demonstrate that arsenene-based heterostructures paired with molybdenum disulfide, tetracyano-quinodimethane, or tetracyanonaphtho-quinodimethane can form type II band alignments. These arsenene-based heterostructures cannot only satisfy all the requirements as photocatalysts for photocatalytic water splitting but can also show an excellent power conversion efficiency of ∼20% as potential photovoltaics.