Tailoring Hydrogen Evolution Reaction with single-atom catalysts on Ti2B MBenes: Insights from computational screening

The utilization of single-atom catalysts (SACs) in the context of the Hydrogen Evolution Reaction (HER) holds significant promise for advancing electrocatalysis. Upon implantation or anchoring on two-dimensional (2D) materials, these catalysts exhibit improved stability, selectivity, and reactivity. This study uses density functional theory-based computational techniques to demonstrate the potential of SACs embedded on novel 2D materials, such as MBenes. To assess their HER activity, the transition metals (TMs) are screened as SACs embedded in Ti2B monolayer. Our results indicate that the inclusion of a single TM can finely adjust hydrogen adsorption, resulting in a characteristic volcano-like pattern, and particularly Pd-Ti2B emerges as a standout candidate, with an optimal Gibbs free energy of -0.057 eV. Moreover, Pd-Ti2B exhibits a notable exchange current density of 1.25 x 10(-4) Acm(-2) surpassing that of numerous traditional metal catalysts, including Pt(111), by approximately 105%. Furthermore, we underscore the electronic characteristics contributing to the extraordinary electrocatalytic activity of a single TM atom encased in Ti2B, viz., Pd-Ti2B, for HER. This study contributes greatly to our understanding of electrocatalytic processes and facilitates the development of potent MBenes-based catalysts for hydrogen evolution.