Unidirectional Electron Transfer on Bismuth-Doped Pt/YMn<sub>2</sub>O<sub>5</sub> for Efficient CO Oxidation as Diesel Oxidation Catalysts
Darong He, Yunfeng Chen, Shanshan Li, Yaxin Liu, Hailong Zhang, Yi Jiao, Ming Zhao, Jianli Wang, Yaoqiang Chen
Abstract
Advanced fuel technology development requires exhaust after-treatment catalysts with low-temperature oxidation properties. For diesel oxidation catalysts (DOCs), reducing competitive oxidation at the key active site Pt in multicomponent exhaust gases (carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NO x )) is the most effective solution to this problem. Here, composite catalysts with multiple active centers of Pt/Bi 3+ -doped YMn 2 O 5 were prepared. And in a competing multicomponent diesel exhaust atmosphere, the complete conversion temperature ( T 100 ) for CO oxidation of the Bi 3+ -doped catalysts was only 210 °C, resulting in a better low-temperature activity for the overall DOCs. In addition, even after severe hydrothermal aging, the T 100 of CO was only 235 °C. This is attributed to the unidirectional electron transfer present in the Pt–O–Bi structure that promotes the rapid oxidation of CO in the low-temperature region and reduces the competing adsorption between CO/HC/NO. Constructing such electron transfer channels to rapidly transform specific molecules provides valuable insights into solving multicomponent competitive reactions.