Insight into the d-p Orbital Hybridization of Ru and B Dispersed g-C₃N₄ Catalysts for Nitrogen Reduction Reaction

Electrochemical nitrogen reduction reaction (NRR) is considered as an important strategy for ammonia using green energy. Single atom catalysts (SACs) with a metal atom as active site have been shown its advantages to high ammonia yield and low energy consumption. In this work, we proposed a new concept of SACs with the capacity of d-p orbital hybridization. These computationally designed SACs contained a metal and non-metal pair anchored on g-C3N4 slab. Among these SACs studied in the present work, RuB@g-C3N4 catalyst performed the best activity for NRR with low onset potential of -0.33 V by a two-step scanning computations using density functional theory (DFT). Moreover, suppressing effectively to the competitive hydrogen evolution reaction (HER) also make it more selective. It was further revealed that the hybridization of d-p orbitals between metal and nonmetal could regulate the electronics of active sites and facilitate the adsorption and charge transfer of adsorbed N-2 molecules resulting in enhanced catalytic performance. This work demonstrated an alternative way to further enhance the catalytic activity of SACs by introducing a non-metal atom.