Decorating CeO2 Nanoparticles on Mn2O3 Nanosheets to Improve Catalytic Soot Combustion

Herein, we synthesized CeO2 nanoparticles-decorated Mn2O3 nanosheets on monolithic Ni foam (Ce/Mn-NF) for catalytic elimination of soot particulates. The macroporous nanostructures created by the Mn2O3 nanosheets improve the soot-catalyst contact efficiency on the external surface of catalysts. The superficial Mn–Ce interaction can produce Mn4+ and oxygen vacancies on the Ce/Mn-NF catalysts through the redox process of Ce4+ + Mn3+ ↔ Mn4+ + Ce3+, simultaneously generating surface active oxygen species. Moreover, our results demonstrate that the surface adsorbed oxygen species induced by the Mn–Ce interaction are more active for catalytic soot oxidation than those on the Mn-NF. Thus, the introduction of the CeO2 nanoparticles to the Mn2O3 nanosheets can significantly improve the catalytic activity for soot combustion. For the Ce/Mn-NF-2, the surface atomic ratio of Ce and Mn is close to 1:1, which will create more Mn–Ce interaction sites to generate active oxygen species compared with other catalysts. Accor...