1e:T4f3,Selective organic transformation under mild conditions constitutes a challenge in green chemistry, especially for alcohol oxidation, which typically requires environmentally unfriendly oxidants. Here, we report a new plasmonic catalyst of Au supported on BiOCl containing oxygen vacancies. It photocatalyzes selective benzyl alcohol oxidation with O₂ under visible light through synergistic action of plasmonic hot electrons and holes. Oxygen vacancies on BiOCl facilitate the trapping and transfer of plasmonic hot electrons to adsorbed O₂, producing •O₂^- radicals, while plasmonic hot holes remaining on the Au surface mildly oxidize benzyl alcohol to corresponding carbon-centered radicals. The hypothesized concerted ring addition between these two radical species on the BiOCl surface highly favors the production of benzaldehyde along with an unexpected oxygen atom transfer from O₂ to the product. The results and understanding acquired in this study, based on the full utilization of hot charge carriers in a plasmonic metal deposited on a rationally designed support, will contribute to the development of more active and/or selective plasmonic catalysts for a wide variety of organic transformations.1f:T4a4,BiOI/TiO2 heterostructures with different Bi to Ti molar ratios were synthesized through a simple soft-chemical method at a temperature as low as 80 °C. The as-prepared powders were characterized by X-ray powder diffraction, electron microscopy, UV−vis diffuse reflectance spectroscopy, nitrogen sorption, and X-ray photoelectron spectroscopy. The photocatalytic activities of these BiOI/TiO2 heterostructures were evaluated on the degradation of methyl orange under visible-light irradiation (λ > 420 nm). The results revealed that the BiOI/TiO2 heterostructures exhibited much higher photocatalytic activities than pure BiOI and TiO2, respectively, and 50%BiOI/TiO2 showed the best activity among all these heterostructured photocatalysts. Surface photovoltage spectroscopy and transient photovoltage measurements were used to confirm the formation of heterojunction and probe charge transfer between BiOI and TiO2. The visible-light photocatalytic activity enhancement of BiOI/TiO2 heterostructures could be attributed to its strong absorption in the visible region and low recombination rate of the electron−hole pairs because of the heterojunction formed between BiOI and TiO2.

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