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

• Published in: Applied catalysis. A, General General, 2022-08, Vol.643, p.118742, Article 118742
• Main Authors: Liang, Yanli, Hu, Chao, Zou, Wei, Ma, Xiaoyan, He, Darong, Wang, Jianli, Zhao, Ming, Chen, Yaoqiang
• Format: Article
• Language: English
• Subjects: Atomic rearrangement; Carbon monoxide; Catalysts; Diesel oxidation catalyst; Mullite; Nanoparticles; Oxidation; Oxidation performance; Oxygen; Platinum; Redox cycles; Stability
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2022.118742

To improve the stability of Pt nanoparticles, the redox cycles with oxidation at 800 °C and reduction at 250 °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 °C, and the NO maximum conversion is improved by 27 % than the catalyst with only oxidation treatment at 800 °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. [Display omitted] •Redox cyclic treatment could strengthen the interaction of Pt with YMn2O5.•Oxygen vacancies anchor platinum sites for reduction at low temperature (250 °C).•The ability of oxygen regeneration is improved for the redox cyclic catalyst.•The formation of bridged/chelating nitrates contribute to NO catalytic performance.•Platinum sites and active oxygen species are favor of the low temperature activity.