Wang Si-Dun, Liu Yi, Ma Tong-Mei, Li Xiao-Na, He Sheng-Gui
State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
China School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China.
Chemphyschem. 2025 Jan 14;26(2):e202400888. doi: 10.1002/cphc.202400888. Epub 2024 Nov 9.
Catalytic NO reduction by CO is imperative to satisfy the increasingly rigorous emission regulations. Identifying the structural characteristic of crucial intermediate that governs the selectivity of NO reduction is pivotal to having a fundamental understanding on real-life catalysis. Herein, benefiting from the state-of-the-art mass spectrometry, we demonstrated experimentally that the CuVO clusters can mediate the catalysis of NO reduction by CO, and two competitive channels to generate NO and N can co-exist. Quantum-chemical calculations were performed to rationalize this selectivity. The formation of the ONNO unit on the Cu dimer was demonstrated to be a precursor from which two pathways of NO reduction start to emerge. In the pathway of NO generation, only the Cu dimer was oxidized and the VO moiety functions as a "support", while both moieties have to contribute to anchor oxygen atoms from the ONNO unit and then N can be generated. This finding displays a clear picture to elucidate how and why the involvement of VO "support" can regulate the selectivity of NO reduction.
通过一氧化碳催化还原一氧化氮对于满足日益严格的排放法规至关重要。确定控制一氧化氮还原选择性的关键中间体的结构特征对于深入理解实际催化过程至关重要。在此，受益于先进的质谱技术，我们通过实验证明了CuVO团簇可以介导一氧化碳对一氧化氮的催化还原，并且生成一氧化氮和氮气的两个竞争通道可以共存。进行了量子化学计算以解释这种选择性。已证明在铜二聚体上形成的ONNO单元是一氧化氮还原的两条途径开始出现的前体。在生成一氧化氮的途径中，只有铜二聚体被氧化，而VO部分起到“载体”的作用，而两个部分都必须有助于锚定来自ONNO单元的氧原子，然后才能生成氮气。这一发现清晰地展示了VO“载体”的参与如何以及为何能够调节一氧化氮还原的选择性。
