Charge-Polarized Interfacial Engineering Enables Radical Management for 1000 h Electrosynthesis of Para-Benzoquinone

Radical-mediated organic electrosynthesis frequently suffers from limited selectivity and catalytic instability, largely arising from uncontrolled radical coupling and overreaction. These challenges intensify under large-current conditions, where accelerated radical generation promotes competing side reactions and undermines practical implementation. Here, we introduce a charge-polarized interfacial engineering strategy to address these issues, demonstrated using a Cr₂O₃/Ru-Fe₂O₃ heterostructure to drive the selective electro-oxidation of phenol to para-benzoquinone (p-BQ). The polarized interface enforces a vertical adsorption configuration of phenoxy radicals, suppressing Langmuir-Hinshelwood polymerization while stabilizing high-valent Ru oxidative centers and facilitating rapid desorption of p-BQ product. As a result, the catalyst achieves 1000 h of continuous p-BQ electrosynthesis at record steady-state current densities above 40-50 mA cm^-2, delivering high product selectivity and parallel hydrogen production at 1.0 V in an asymmetric hybrid seawater electrolyzer. This work establishes interfacial radical management as an effective framework for efficient electrosynthesis of value-added chemicals.