Hydroxyl-Defined Lewis Base Interface Directs Hole Routing in Cooperative Photoredox Catalysis

Abstract Directing photogenerated carriers toward productive coupled redox chemistry is central to solar-to-chemical energy conversion, yet the interfacial chemical basis governing carrier routing remains elusive. Here, we establish a hydroxyl-defined Lewis base interface as a chemically programmed platform for coupling hole-selective extraction with cooperative photoredox catalysis. By in situ constructing crystalline In(OH)3 on ultrathin ZnIn2S4 nanosheets (ZISO), a hydroxyl-associated interfacial architecture enriched with lattice hydroxyl Lewis base sites is created, enabling selective regulation of oxidation-side carrier dynamics. Femtosecond transient spectroscopic and surface photovoltage measurements reveal that the hydroxyl-defined interface promotes hole-selective interfacial extraction, suppresses charge recombination, and preserves reduction-side electron population for the reduction reaction. Consequently, photooxidative thiophenol valorization via dehydrogenative coupling proceeds at a rate of 33.5 mmol g–1 h–1 and is efficiently integrated with CO2 photoreduction in a cooperative photoredox process. Density functional theory calculations further show that the hydroxyl-defined interface generates cooperative adsorption configurations that promote electronic polarization and substrate activation, stabilize key reaction intermediates, and lower the energetic requirements for CO2 reduction. As a result, the hydroxyl-defined interface translates directional carrier dynamics into interfacial redox turnover, enabling efficient cooperative photoredox catalysis. This work reveals that chemically explicit interfacial functionality can be leveraged to integrate carrier-selective routing and catalytic redox chemistry, providing an interfacial design principle for cooperative photoredox systems in solar-to-chemical energy conversion.