Promoting N electroreduction to ammonia by fluorine-terminating TiCT MXene.

Two-dimensional MXene-based materials are potential of presenting unique catalytic performances of electrocatalytic reactions. The surface functionalization of MXene-based catalysts is attractive for developing efficient electrocatalysts toward nitrogen reduction reaction. Herein, we reported a TiCT MXene with a medium density of surface functionalized fluorine terminal groups, as an excellent N reduction reaction electrocatalyst with enhanced adsorption and activation of N. The TiCT MXene catalyst showed a production rate of ammonia as 2.81 × 10 μmol·s·cm, corresponding to a partial current density of 18.3 μA·cm and a Faradic efficiency of 7.4% at - 0.7 V versus reversible hydrogen electrode in aqueous solutions at ambient conditions, substantially exceeding similar TiCT MXene catalysts but with higher or lower densities of surface fluorine terminal groups. Our work suggests the capability of developing surface functionalization toolkit for enhancing electrochemical catalytic activities of two-dimensional MXene-based materials.