Can graphene with intrinsic defects electrocatalyze N2 to NH3 reduction?

Defect engineering strategy is widely adopted to design graphene/ graphene-composited N-2 reduction reaction (NRR) electrocatalysts. Currently, all attentions are focused on the introduction of extrinsic defects for graphene, but the intrinsic defects of graphene are ignored even though they would be commonly introduced in the procedures of preparation and processing. Herein, the effect of intrinsic defects of graphene (dislocation, vacancy and edge defects) on NRR is studied by density functional theory (DFT) calculation firstly. Graphene with armchair and zigzag edges shows inert for NRR due to the unfavourable N-2 capture. For the graphene with vacancy and dislocation defects, the two configurations exhibit favourable N-2 capture (negative N-2 adsorption free energies), acceptable energy barriers at the potential-determining step and high NRR selectivity. This work would remind researchers that the effect of intrinsic defects of graphene cannot be ignored when analyzing the source of NRR performance, and provides a brand-new potential paradigm to design graphene/graphene-composited NRR electrocatalysts.