Exploring the dynamic evolution of lattice oxygen on exsolved-Mn2O3@SmMn2O5 interfaces for NO Oxidation
Lattice oxygen in metal oxides plays an important role in the reaction of diesel oxidation catalysts, but the atomic-level understanding of structural evolution during the catalytic process remains elusive. Here, we develop a Mn<sub>2</sub>O<sub>3</sub>/SmMn<sub>2</sub>O<sub>5</sub> catalyst using a non-stoichiometric exsolution method to explore the roles of lattice oxygen in NO oxidation. The enhanced covalency of Mn-O bond and increased electron density at Mn<sup>3+</sup> sites, induced by the interface between exsolved Mn<sub>2</sub>O<sub>3</sub> and mullite, lead to the formation of highly active lattice oxygen adjacent to Mn<sup>3+</sup> sites. Near-ambient pressure X-ray photoelectron and absorption spectroscopies show that the activated lattice oxygen enables reversible changes in Mn valence states and Mn-O bond covalency during redox cycles, reducing energy barriers for NO oxidation and promoting NO<sub>2</sub> desorption via the cooperative Mars-van Krevelen mechanism. Therefore, the Mn<sub>2</sub>O<sub>3</sub>/SmMn<sub>2</sub>O<sub>5</sub> exhibits higher NO oxidation activity and better resistance to hydrothermal aging compared to a commercial Pt/Al<sub>2</sub>O<sub>3</sub> catalyst.
Authors
- Yimin A. Wu (ORCID: https://orcid.org/0000-0002-3807-8431)
- Qilei Yang (ORCID: https://orcid.org/0000-0001-7906-7264)
- Shouhua Feng (ORCID: https://orcid.org/0000-0001-6888-068X)
- Junhua Li (ORCID: https://orcid.org/0000-0002-3857-390X)
- Chuan Gao (ORCID: https://orcid.org/0000-0002-1165-7185)
- Carl Redshaw (ORCID: https://orcid.org/0000-0002-2090-1688)
- Yue Peng (ORCID: https://orcid.org/0000-0001-5772-3443)
- Shucheng Shi (ORCID: https://orcid.org/0000-0003-4568-9369)
- Xuefeng Chu (ORCID: https://orcid.org/0000-0003-1472-8185)
- Yongliang Ma
- Hui Zhang (ORCID: https://orcid.org/0000-0002-1719-4345)
- Xiyang Wang (ORCID: https://orcid.org/0000-0002-7591-6676)
- Zhen Li (ORCID: https://orcid.org/0000-0001-7871-1193)
- Xinbo Li (ORCID: https://orcid.org/0000-0002-1628-1033)
Institutions
- University of Waterloo (CA)
- University of Hull (GB)
- Jilin University (CN)
- Chinese Academy of Sciences (CN)
- ShanghaiTech University (CN)
- Shanghai Institute of Microsystem and Information Technology (CN)
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry
- Tsinghua University (CN)
Publication Details
- Journal
- Nature Communications
- Published
- 2024-09-02
- DOI
- https://doi.org/10.1038/s41467-024-51473-9
- Citations
- 37
- Primary Topic
- Catalytic Processes in Materials Science
- Type
- article
- Field-Weighted Citation Impact
- 4.33
Funders
- University of Hull
- Salt Science Research Foundation
- National Natural Science Foundation of China
- Natural Sciences and Engineering Research Council of Canada