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The substitution of base-metal oxides for noble metals is a great challenge for catalysts, sensors, and other functional materials. In this work, the dynamic structure at the interface of binary metal oxides, as a popular natural phenomenon in material science and catalysis, was studied in detail in the case of a binary copper–ceria species (CuOx-CeO2). The catalytic activity of CuOx-CeO2 could be largely improved by doping indium oxide (In2O3). The reaction rate of 1.26 × 10–5 molCO gcat.–1 s–1 for a 1.25In5Cu/CeO2 catalyst toward CO oxidation is 12 times higher than that from commercial Pd catalysts. In addition, the indium-doped catalyst shows strong resistance to CO2 and H2O poisoning. We determined the dynamic interfacial structure of CuOx/CeO2 catalysts induced by In2O3 during CO oxidation using in situ techniques, intrinsic kinetics, and density functional theory calculations (DFT). Indeed, the surface of CuOx particles could be reconstructed through the interaction with In2O3. Such an interaction ...

Mn3O4@SiO2 prepared via a Stober route showed a steady reaction rate for CO oxidation at 250 °C after 12 h. The reaction orders, with respect to CO (0.49–0.12) and O2 (0.4–0.6), were obtained for a Mn3O4@SiO2 catalyst (dMn3O4 = 7.6 nm) in the temperature range of 220–280 °C. Via Operando Raman spectroscopy, a COad-induced change in the symmetric stretch of Mn–O–Mn (from 636 cm–1 to 642 cm–1) was observed for Mn3O4@SiO2, indicating a tiny structure modification of core Mn3O4 by the adsorption of CO. With the combination of the catalyst structure and the kinetics of CO oxidation, we assume that this reaction proceeds mainly through the Langmuir–Hinshelwood mechanism at or below 280 °C. In comparison with the reference α-Mn2O3 catalyst, the presence of shell SiO2 does not change the reaction behavior but improves the catalyst stability.