Overcoming Mass‐Transport Limitations in Electrocatalytic Dehalogenation via DMSO‐Engineered Hydrogen Bonds

ABSTRACT Electrocatalytic conversion of water‐soluble organics in aqueous media offers a sustainable route to high‐value chemicals, yet sluggish mass transport remains a critical bottleneck at industrially relevant current densities. Here, dimethyl sulfoxide (DMSO) is employed as the modifier to enhance mass transport by reconstructing hydrogen‐bond (H‐bond) networks. In the bulk electrolyte, DMSO inserts into the dense hydrogen bonds to expand the free‐volume distribution, releasing reactants from the solvation shell and accelerating their diffusion. Simultaneously, interfacial interactions between DMSO, reactants, and cations enrich local reactant concentrations, cooperatively facilitating the reaction kinetics. This dual‐enhancement mechanism achieves ∼60% Faradaic efficiency (FE) in electrocatalytic dehalogenative hydrogenolysis at 300 mA cm −2 . Our strategy demonstrates broad utility across the dehalogenative hydrogenation of other halogenated substrates and the hydrogenation of nitriles/nitro compounds, delivering >10% FE improvements. By coupling bulk diffusion acceleration with interfacial reactant enrichment, this work offers a promising strategy to overcome mass transport limitations in aqueous electrosynthesis.