Reconstructing Hydrogen‐Bond Network for Efficient Acidic Oxygen Evolution

Developing highly active oxygen evolution reaction (OER) catalysts in acidic conditions is a pressing demand for proton‐exchange membrane water electrolysis. Manipulating proton character at the electrified interface, as the crux of all proton‐coupled electrochemical reactions, is highly desirable but elusive. Herein we present a promising protocol, which reconstructs a connected hydrogen‐bond network between the catalyst‐electrolyte interface by coupling hydrophilic units to boost acidic OER activity. Modelling on N‐doped‐carbon‐layer clothed Mn‐doped‐Co3O4 (Mn−Co3O4@CN), we unravel that the hydrogen‐bond interaction between CN units and H2O molecule not only drags the free water to enrich the surface of Mn−Co3O4 but also serves as a channel to promote the dehydrogenation process. Meanwhile, the modulated local charge of the Co sites from CN units/Mn dopant lowers the OER barrier. Therefore, Mn−Co3O4@CN surpasses RuO2 at high current density (100 mA cm−2 @ ~538 mV).