Furfuryl Alcohol‐Driven Proton Supply Enables Efficient Photocatalytic H ₂ O ₂ Production Beyond Water‐Based Systems

ABSTRACT Photocatalytic H ₂ O ₂ production via the two‐electron oxygen reduction reaction is often limited by rapid charge recombination and insufficient proton supply in aqueous systems. Here, we construct a covalently linked ZnIn ₂ S ₄ ‐carbon dots (ZIS‐CDs) develop a coupled system that integrates H ₂ O ₂ generation with selective oxidation of furfuryl alcohol (FFA). The built‐in electric field in the ZIS‐CDs heterojunction enables efficient charge separation. FFA acts simultaneously as a sacrificial electron donor, oxidation substrate, and proton source in the ultra‐dry acetonitrile (ACN)‐FFA system. During its oxidation, FFA supplies protons for H ₂ O ₂ generation and is selectively converted into furoic acid (FA). This dual regulation of charge transfer and proton supply leads to an H ₂ O ₂ production rate of 24 mmol·g ^{− 1} ·h ^{− 1} , an apparent quantum yield of 14.57% at 400 nm, and a solar‐to‐chemical conversion efficiency of 1.78%, with 100% selectivity and 98% conversion to furoic acid. This work introduces a new strategy that couples organic transformation with proton management to enhance photocatalytic H ₂ O ₂ synthesis.