Angewandte Chemie International Edition · 2023 · 58 citations · 21 references
Natural SciencesChemical EngineeringChemistryCatalysisChemical KineticsTheoretical ChemistryCatalyst CharacterizationCatalyst DesignCatalytic MaterialsCatalytic MechanismsCatalytic Reaction KineticsRedox CatalysisActive SitesCatalyst Active SitesCatalyst DevelopmentCatalytic Reaction MechanismsCo OxidationMechanistic ElucidationReaction Mechanism ElucidationSingle-atom Catalysis
Abstract Elucidating the reaction mechanism in heterogeneous catalysis is critically important for catalyst development, yet remains challenging because of the often unclear nature of the active sites. Using a molecularly defined copper single‐atom catalyst supported by a UiO‐66 metal–organic framework (Cu/UiO‐66) allows a detailed mechanistic elucidation of the CO oxidation reaction. Based on a combination of in situ/operando spectroscopies, kinetic measurements including kinetic isotope effects, and density‐functional‐theory‐based calculations, we identified the active site, reaction intermediates, and transition states of the dominant reaction cycle as well as the changes in oxidation/spin state during reaction. The reaction involves the continuous reactive dissociation of adsorbed O 2 , by reaction of O 2,ad with CO ad , leading to the formation of an O atom connecting the Cu center with a neighboring Zr 4+ ion as the rate limiting step. This is removed in a second activated step.
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The Chemistry and Applications of Metal-Organic Frameworks
Hiroyasu Furukawa, Kyle E. Cordova, M. O’Keeffe et al. · Science · 2013 · 16.5K citations