Role of Specific N‐Containing Active Sites in Interconnected Graphene Quantum Dots for the Enhanced Electrocatalytic Activity towards Oxygen Evolution Reaction

Abstract

Abstract 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 RuO 2 . More precisely, the unexpected behaviour of graphene quantum dots towards oxygen evolution reaction (OER) is attributed to the interconnection through N‐rich 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 π‐π 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.