Can Single Metal Atoms Trapped in Defective h-BN/Cu(111) Improve Electrocatalysis of the H2 Evolution Reaction?

Metal-supported hexagonal boron nitride monolayers (h-BN/M) are emerging as new potential electrocatalysts for various energy-related oxidation or reduction process. So far, several preparation methods have been developed to introduce, in a controlled way, defects such as vacancies or substitutional heteroatoms. Herein, we investigate by dispersion-corrected density functional theory (DFT) calculations, defective and metal-doped h-BN/Cu(111) systems as electrocatalysts for the hydrogen evolution reaction (HER). By calculating the hydrogen binding energy (ΔG*H) at different coverage conditions, we observe how the interaction between the defective/metal-doped h-BN layer and the Cu(111) substrate plays a key role in tuning the reactivity, leading to a thermoneutral hydrogen adsorption step (i.e., ΔG*H ≈ 0). These results could be generalized to other h-BN/M interfaces and may help their rational design for an improved H2-evolving electrocatalysis.