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Plasmonic O₂ dissociation and spillover expedite selective oxidation of primary C-H bonds.

ABSTRACT: Manipulating O₂ activation via nanosynthetic chemistry is critical in many oxidation reactions central to environmental remediation and chemical synthesis. Based on a carefully designed plasmonic Ru/TiO_2-x catalyst, we first report a room-temperature O₂ dissociation and spillover mechanism that expedites the "dream reaction" of selective primary C-H bond activation. Under visible light, surface plasmons excited in the negatively charged Ru nanoparticles decay into hot electrons, triggering spontaneous O₂ dissociation to reactive atomic ˙O. Acceptor-like oxygen vacancies confined at the Ru-TiO₂ interface free Ru from oxygen-poisoning by kinetically boosting the spillover of ˙O from Ru to TiO₂. Evidenced by an exclusive isotopic O-transfer from ¹⁸O₂ to oxygenated products, ˙O displays a synergistic action with native ˙O₂ ^- on TiO₂ that oxidizes toluene and related alkyl aromatics to aromatic acids with extremely high selectivity. We believe the intelligent catalyst design for desirable O₂ activation will contribute viable routes for synthesizing industrially important organic compounds.

SUBMITTER: Li H

PROVIDER: S-EPMC8635223 | biostudies-literature |

REPOSITORIES: biostudies-literature

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