Modulated synthesis of MnO2-decorated Fe–Mn composite oxides：synergistic effects on boosting the performance of toluene oxidation

MnO2-decorated iron-manganese composite oxides were prepared via a novel method combining hydrolysis driving redox reaction and hydrothermal approach. The differences in physicochemical properties and microstructures were controlled by modulating the ratio of MnO2 to 5Mn1Fe (The molar ratio of Mn to Fe was 5:1). Characterization results displayed that the excellent efficiency of toluene removal over 3MnO2/5Mn1Fe catalyst was attributable to the special structure, strong low-temperature reducibility, high surface Mn3+/Mn4+ and Oads/Olatt molar ratios. The interaction between MnO2 and 5Mn1Fe played a predominant role in outstanding catalytic efficiency of the hetero-nanostructures. Among all as-prepared catalysts, the highest activity was achieved over the bayberry-like 3MnO2/5Mn1Fe catalyst with corresponding T90 of 233 °C, much lower than MnO2 for 313 °C and 5Mn1Fe for 280 °C. This successful strategy could not only be applied to VOCs catalytic oxidation but also provide a novel synthetic path for other catalysis systems.