▎ 摘　　要

Electrochemical water oxidation is a dynamic and basal approach for several energy conversion technologies such as solar fuels and metal-air batteries. Herein, we report a novel ` nitrogen' (N) enriched interconnected graphene quantum dots (C-GQDs) as efficient oxygen evolution electrocatalyst, a potential candidate to replace the noble metal OER electrocatalysts. Interestingly, C-GQDs deliver a current density of 10 mAcm(-2) at 350 mV, a small Tafel slope of 55 mV/dec and outstanding durability which is much superior to the state-of-the-art precious RuO2. More precisely, the unexpected behaviour of graphene quantum dots towards oxygen evolution reaction (OER) is attributed to the interconnection through Nrich framework (25 %) among the discrete particles. Predominantly, in the pyridine N-oxide, N acts as nucleophilic site and pyridinic N develops p-type doping, responsible for enhanced the OER electrocatalytic activity. The co-existence of both pyridinic N and pyridine N-oxide N induces charge redistribution through p-p delocalization to reduce the * OOH thermodynamic energy barrier. We hope that our study will encourage to develop more efficient electrocatalysts with more effective doping or surface functionalized structure by understanding the dopant nature.