Theoretical Evaluation of Possible 2D Boron Monolayer in N-2 Electrochemical Conversion into Ammonia

This work aims to explore inorganic boron as an electrochemical catalyst for nitrogen reduction reaction (NRR). The density functional theory approach has been employed to evaluate the free-energy profile for NRR on two stable boron monolayer types (alpha and beta(12)). Our results revealed that the rate-determining step for nitrogen reduction to ammonia over two-dimensional boron structures is the first reduction step. Hexagonal triangular boron atoms in the alpha-sheet exhibit the best catalytic performance in all possible positions on the boron monolayer sheet surface, with a maximum energy input of 0.77 eV vs stand hydrogen electrode.