Two-phase interfacial photocatalysis via amphiphilic Bi2WO6 to facilitate synchronous production and spontaneous separation of H2O2 and value-added organics

Photocatalytic synthesis of H 2 O 2 from O 2 reduction coupled with selective oxidation of organics into value-added chemicals is highly appealing; however, the troubling separation process presents a technical difficulty when both H 2 O 2 and organic products are obtained in a homogeneous solution. Herein, an amphiphilic Bi 2 WO 6 catalyst was synthesized through a facile solvothermal method based on the synergetic modification with both hydrophobic and hydrophilic groups, which enables the construction of Pickering emulsion interfacial photocatalysis systems in various organic/water mixtures to facilitate synchronous production and spontaneous separation of H 2 O 2 and value-added organics. The amphiphilic Bi 2 WO 6 catalyst exhibited significantly enhanced photocatalytic performance compared to its oleophilic and hydrophilic counterparts, resulting in remarkable generation rates of H 2 O 2 and benzaldehyde reaching up to 121.53 and 99.25 mmol g −1 h −1 , respectively, in a benzyl-alcohol/water biphasic system under simulated sunlight. The excellent photocatalytic performance could be maintained in a long-term reaction process. The photocatalytic mechanism was investigated through various control experiments and detailed characterizations. The interfacial photocatalysis played a crucial role in accelerating the redox reactions, showcasing its favorable applicability in various organic/water biphasic systems. This study provides guidelines for the realization of interfacial photocatalysis assisted by amphiphilic semiconductors, opening up a novel strategy to the simultaneous production of solar fuels and organic chemicals.