First-principles study on Fe2B2 as efficient catalyst for nitrogen reduction reaction

The efficient and stable electrocatalysts of Fe2B2 can promote N2 adsorption and accelerate electron transfer using an enzymatic mechanism to activate the NRR with lower limiting potential (−0.44 V). [Display omitted] Ammonia (NH3) is considered an attractive candidate as a clean, highly efficient energy carrier. The electrocatalytic nitrogen reduction reaction (NRR) can reduce energy input and carbon footprint; therefore, rational design of effective electrocatalysts is essential for achieving high-efficiency electrocatalytic NH3 synthesis. Herein, we report that the enzymatic mechanism is the more favourable pathway for NRR, due to lower limiting potential (−0.44 V), lower free energy (only 0.02 eV) of the first hydrogenation step (*N–N to *NH–N), and more electron transfer from Fe2B2 to the reaction species. In addition, both vacancies and dopants can be helpful in reducing the reaction energy barrier of the potential-determining step. Therefore, we have demonstrated that Fe2B2 is a potential new candidate for effective NRR and highlighted its potential for applications in electrocatalytic NH3 synthesis.