Unlocking Stable H2O2 Electrosynthesis by Passivating Defects in Reduced Graphene Oxide.

Electrochemical synthesis of hydrogen peroxide (H2O2) on carbon-based catalysts often faces a persistent activity-stability dilemma: while defects can enhance catalytic activity, they frequently overstabilize the *OOH intermediate, leading to O-O bond cleavage and consequent radical-induced degradation of the catalyst. To address this challenge, we engineered an asymmetric O-Si-N-C structure at the interface between amorphous SiOx and nitrogen-doped reduced graphene oxide (Si-N-rGO), thereby electronically regulating adjacent carbon sites to weaken excessive *OOH adsorption. Combined experimental studies and microkinetic modeling show that electronegative nitrogen acts as an electron buffer, redistributing the local charge density across the O-Si-N-C interface through spatial charge transfer. This electronic adjustment weakens excessive *OOH binding and brings its adsorption free energy into a moderate Sabatier region, facilitating efficient oxygen activation and smooth product desorption via a proton-coupled electron transfer pathway, effectively suppressing radical-mediated structural degradation. As a result, the Si-N-rGO catalyst operates stably for over 160 h at an industrial current density of 300 mA cm-2 in a flow cell, continuously producing 5.0 wt % H2O2 with a Faradaic efficiency of 80%. These findings offer a design strategy for developing durable catalysts toward industrial-scale electrosynthesis of H2O2.