Enhanced the Catalytic Performance of Samarium and Cerium Co-Modified Mn-Based Oxide Catalyst for Soot Oxidation

Manganese-based oxides with good redox properties exhibit high soot oxidation activity. To further enhance their catalytic performance, introducing additional metal elements into manganese-based oxides is considered an effective approach. Herein, two rare earth elements (Sm and Ce)-modified MnOx catalysts were prepared by the co-precipitation method. The synthesized MnOx catalyst primarily consists of the Mn3O4 phase, with trace amounts of Mn5O8. The addition of Sm or Ce maintains the predominance of the Mn3O4 phase, increases the proportion of Mn5O8, and enhances the redox properties, thereby boosting the catalytic activity for NO and soot oxidation. Notably, the coexistence of Sm and Ce achieves optimal soot oxidation activity, with T10 reaching 306 °C. Comprehensive physicochemical characterization elucidates the underlying structure–performance relationships of these catalysts.