Bicarbonate-Promoted Hydrogen Peroxide Activation for Selective Electrochemical Oxidation of Small Molecules

H 2 O 2 is a green oxidant of broad importance, but its mild reactivity limits its practical utilization. Conventional activation strategies, such as Fenton chemistry or zeolite-mediated processes, are constrained by nonselectivity in the former and mass-transfer limitations in the latter due to their heterogeneous nature, and both are typically effective only under acidic conditions. Here, we report a homogeneous bicarbonate-promoted H 2 O 2 activation strategy that can be seamlessly integrated with electrochemical H 2 O 2 generation to enable the electron oxidation of small organic molecules in neutral media. Under ambient conditions, bicarbonate reacts with H 2 O 2 to form peroxycarbonate, which subsequently dissociates to produce multiple reactive oxygen species. Coupling this chemistry with electrochemical H 2 O 2 production via the two-electron oxygen reduction reaction, the cascade system efficiently oxidizes dimethyl sulfoxide and other representative organic substrates to their corresponding products at industrially relevant current density (up to 250 mA cm –2 ), with low working potentials (>1 V lower than direct electrochemical oxidation) and high apparent Faradaic efficiencies (up to 85%) under neutral conditions. Owing to the low cost and wide availability of bicarbonate, this strategy provides a scalable and versatile platform for selective electrochemical oxidation of small molecules into value-added chemicals.