Decorating CeO₂ Nanoparticles on Mn₂O₃ Nanosheets to Improve Catalytic Soot Combustion

Abstract

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. Accordingly, it exhibits higher catalytic activity. The tactful design of the MnO x –CeO2 catalysts successfully overcomes the problems of how to construct macroporous nanostructures with mixed metal oxides, and this strategy of material design may be applied in other related catalytic systems.

Solvent-free liquid-phase selective catalytic oxidation of toluene to benzyl alcohol and benzaldehyde over CeO2–MnOx composite oxides

“…The peaks at binding energies of 640.9 and 642.0 eV are correlated with the existence of Mn 2+ and Mn 3+ , respectively. 48,49 The other peak at 646.0 eV is attributed to the satellite peak. 48,50 Fig.…”

“…48,49 The other peak at 646.0 eV is attributed to the satellite peak. 48,50 Fig. 5D shows the O 1s spectra of the samples, which are fitted to three peaks (529.2, 531.3 and 533.9 eV), which are assigned to the lattice oxygen, the chemisorbed oxygen and the physically adsorbed H 2 O, respectively.…”

Novel Bamboo-Mediated Biosynthesis of MnOx for Efficient Low-Temperature Propane Oxidation

“…Temperature-programmed reduction of hydrogen was used to study the redox properties of MnO x , and the results are displayed in Figure A. MnO x -N shows three reduction peaks: the reduction of MnO x to Mn 2 O 3 at 340 °C (peak I), the reduction of Mn 2 O 3 to Mn 3 O 4 at 434 °C (peak II), and the reduction of Mn 3 O 4 to MnO at 497 °C (peak III) . After modification by BP, the reduction peaks shift to a lower temperature, possibly owing to a smaller average particle size of MnO x .…”

Roles of Oxygen Vacancies of CeO2 and Mn-Doped CeO2 with the Same Morphology in Benzene Catalytic Oxidation

“…Among the transition metals doped catalysts, Mn-based catalysts are widely used in the field of environmental catalysis [17,18]. It is reported that Mn-dopedCeO 2 has been applied in the abatement of contaminants, such as the catalytic reduction of NO and diesel soot combustion, which exhibit excellent catalytic activity [19][20][21][22][23].…”