Effects of Synthesis Routes on the States and Catalytic Performance of Manganese Oxides Used for Diesel Soot Combustion

The catalyst obtained through the co-precipitation of Mn(Ac)(2) and (NH4)(2)CO3 (denoted as Mn-Ac-NH4) displays the highest performance for soot oxidation. Compared with other MnOx catalysts, the catalyst Mn-Ac-NH4 exhibits much better reducibility and more uniform sponge-like nanostructure. The characterization results indicate that the oxygen species on the surface of Mn-Ac-NH4 are more active for soot combustion. The NO species can also be captured and oxidized by these oxygen species, generating more reactive NO2 which can enhance soot oxidation.