Single-atom transition metals doping two-dimensional BXN materials (X = 2, 3, 5) with promising electrocatalytic activity for efficient hydrogen production in the entire pH range†
Abstract
Two-dimensional (2D) boron nitrides (BN) have been eagerly and widely used and have tremendous potential in several advanced fields, such as energy harvesting and storage. Due to their significant electronic properties, they are also commonly used as substrates for single-atom catalysts (SACs). Therefore, with the aid of a computer, we designed SACs by doping isolated single atoms of 3d, 4d, and 5d transition metals (TM) on 2D BXN materials (X = 2, 3, 5). In addition, pH regulation is considered to improve the electrocatalytic hydrogen evolution reaction (HER) activity, and the materials’ effectiveness was investigated theoretically based on density functional theory (DFT) calculations. Our results indicate that the low-cost TM SACs can effectively enhance the HER catalytic performance over a wide range of pH. Among all the SACs studied, Ti-, V-, Y- and Zr@B5N show excellent catalytic activity at pH = 0, with the Gibbs free energy change (ΔGH*) of hydrogen adsorption of −0.027, −0.094, 0.073 and −0.040 eV, respectively. We find that Sc- and Y-embedded B2N, Co-, Fe-, and Mo-embedded B3N and Co-, Cr-, V-, Ti-, Y-, Zr-, Nb-, Ru-, and Tc-embedded B5N SACs have excellent catalytic activity in acidic conditions, while Ir-embedded B5N shows high catalytic activity in alkaline conditions. Interestingly, Ti@B2N, Mn@B3N, Fe@B5N and Mo@B5N SACs are highly active in either acidic or alkaline environments. Our work opens new avenues for designing cost-effective SACs with wide-pH-range HER performance.