Revealing OH species in situ generated on low-valence Cu sites for selective carbonyl oxidation.

ABSTRACT: Catalytic oxidation through the transfer of lattice oxygen from metal oxides to reactants, namely the Mars-van Krevelen mechanism, has been widely reported. In this study, we evidence the overlooked oxidation route that features the in situ formation of surface OH species on Cu catalysts and its selective addition to the reactant carbonyl group. We observed that glucose oxidation to gluconic acid in air (21% O₂) was favored on low-valence Cu sites according to X-ray spectroscopic analyses. Molecular O₂ was activated in situ on Cu⁰/Cu⁺ forming localized, adsorbed hydroxyl radicals (*OH) which played the primary reactive oxygen species as confirmed by the kinetic isotope effect (KIE) study in D₂O and in situ Raman experiments. Combined w

SUBMITTER: Cao Y 

PROVIDER: S-EPMC11494291 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature