Atomic rearrangement on YMn2O5 modified Pt-based diesel oxidation catalyst for promoted performance

To improve the stability of Pt nanoparticles, the redox cycles with oxidation at 800 degrees C and reduction at 250 degrees C for three times were adopted on the Mn-mullite doped Pt-based catalysts (Pt-YMO/SA-Red) to rearrange the Pt atoms. The light-off temperature toward CO/C3H6/NO oxidation on Pt-YMO/SA-Red decreases by 20-60 degrees C, and the NO maximum conversion is improved by 27 % than the catalyst with only oxidation treatment at 800 degrees C (Pt-YMO/SA-Oxi). Characterization results verify that the interaction of Pt with YMn2O5 on Pt-YMO/SA-Red is reinforced via redox cyclic treatment to inhibit the aggregation of platinum particles and promote the formation of active oxygen species, in comparison to Pt-YMO/SA-Oxi. The easier active oxygen regeneration and more active platinum sites contribute to the excellent catalytic performances and stability. In addition, the mechanism for the high CO/C3H6/NO oxidation performance are analyzed via the detected reaction intermediate species.