Oxygen Groups Enhancing the Mechanism of Nitrogen Reduction Reaction Properties on Ru- or Fe-Supported Nb2C MXene

To rationally design electrocatalysts with high promising performance is essential for the nitrogen reduction reaction (NRR). Using the first principle density functional theory and ab initio molecular dynamic calculations, we systematically explored the activity, selectivity, and thermodynamic stability of the single-atom or tetra-nuclear metal clusters of Fe and Ru supported on Nb2C MXene modified by oxygen (fluorine) functional groups, resulting in one excellent electrocatalyst (labeling as Ru/Nb2CO2) for NRR. The obtained Ru/Nb2CO2 catalyst mainly undergoes electroreduction of nitrogen that proceeds via an enzymatic hybrid mechanism due to high selectivity (99.9%) and low ΔGPDS (ΔGPDS = 0.59 eV), and the catalyst also has superior stability at 500 K, suggesting Ru/Nb2CO2 has high promising performance for electrocatalytic synthesis of ammonia.