Basic Evidence of the Molecular Dispersion of MnCeO x Catalysts Synthesized via a Novel “Redox-Precipitation” Route

A novel synthesis route driving redox-precipitation reactions among MnVII, CeIII, and MnII precursors in basic aqueous solution yields MnCeO x catalysts (Mnat/Ceat, 0.33−2.0) with a (quasi)molecular dispersion of the active phase and enhanced textural properties in comparison to the conventional coprecipitation method. The basic characteristics of the redox-precipitation process leading to a solid architecture missing a substantial “long-range” crystalline order are discussed. With an excellent reproducibility and irrespective of the Mnat/Ceat ratio, the redox-precipitation method also ensures unchanged textural, structural, and chemical properties of the MnCeO x catalysts. As a much improved dispersion of the active phase, the redox-precipitation route greatly promotes the redox behavior and the surface affinity toward gas-phase oxygen of the MnCeO x system.