Two Dimensional h‐BN/CdS Heterostructure as a Promising Water‐splitting Photocatalyst

This research calculates the structural, optical, and electronic properties of original and strained hexagonal boron nitride/cadmium sulfide (h-BN/CdS) heterostructures using a hybrid density functional method. The electron transfer from CdS to h-BN sheet leads to the formation of electric field across the interface, which is beneficial for efficient separation of electron-hole pairs. The bandgaps of heterostructures decrease with the increase in the strain. In addition, biaxial strain can obviously tune the bandgaps and band alignments of h-BN/CdS heterostructures. The heterostructures in the strain range from 0% to 6% possess suitable bandgaps for visible light utilization and appropriate band alignments for spontaneous production of hydrogen and oxygen. Especially, the original, -2% strained, and 2% strained h-BN/CdS heterostructures can be easy to form due to the negative interface formation energy. The original and 2% strained h-BN/CdS heterostructures are potential candidates as water-splitting photocatalysts.