Three-dimensional (3D) hierarchical Mn2O3 catalysts with the highly efficient purification of benzene combustion

A series of Mn2O3 catalysts were prepared by different hydrothermal temperatures and employed to the catalytic oxidation of benzene due to their high activity. The Mn-120 sample with three-dimensional (3D) hierarchical cube-like morphology mainly exposed (2 1 1) crystal plane exhibited the best catalytic activity for the oxidation of benzene and achieved the benzene conversion of 90% at 248 °C. Meanwhile, the best catalytic performance of the Mn-120 sample was attributed to the most amounts of the Mn3+ species and surface-adsorbed oxygen. With the increase of Mn3+ species, the oxygen binding capacity of Mn-120 was reduced, which could increase its oxygen mobility. The abundant adsorbed oxygen species of Mn-120 could improve the replenishment capacity of lattice oxygen species, and the reaction pathway of catalytic oxidation of benzene over MnO2 obeyed the Mars-Van-Krevelen (MVK) mechanism.