A single site ruthenium catalyst for robust soot oxidation without platinum or palladium
Yuanfeng Li, Tian Qin, Yuechang Wei, Jing Xiong, Peng Zhang, Kezhen Lai, Hongjie Chi, Xi Liu, Liwei Chen, Xiaolin Yu, Zhen Zhao, Lina Li, Jian Liu
Abstract
Abstract The quest for efficient non-Pt/Pd catalysts has proved to be a formidable challenge for auto-exhaust purification. Herein, we present an approach to construct a robust catalyst by embedding single-atom Ru sites onto the surface of CeO 2 through a gas bubbling-assisted membrane deposition method. The formed single-atom Ru sites, which occupy surface lattice sites of CeO 2 , can improve activation efficiency for NO and O 2 . Remarkably, the Ru 1 /CeO 2 catalyst exhibits exceptional catalytic performance and stability during auto-exhaust carbon particle oxidation (soot), rivaling commercial Pt-based catalysts. The turnover frequency (0.218 h −1 ) is a nine-fold increase relative to the Ru nanoparticle catalyst. We further show that the strong interfacial charge transfer within the atomically dispersed Ru active site greatly enhances the rate-determining step of NO oxidation, resulting in a substantial reduction of the apparent activation energy during soot oxidation. The single-atom Ru catalyst represents a step toward reducing dependence on Pt/Pd-based catalysts.