Environmental Catalysis for NO<sub><i>x</i></sub> Reduction by Manipulating the Dynamic Coordination Environment of Active Sites
Lupeng Han, Xiyang Wang, Fuli Wang, Yongjie Shen, Hengxiang Zhang, Weiwei Hu, Min Gao, Yimin A. Wu, Ming Xie, Jianfu Chen, Dengsong Zhang
Abstract
Nowadays, it is challenging to achieve SO 2 -tolerant environmental catalysis for NO x reduction because of the thermodynamically favorable transformation of reactive sites to inactive sulfate species in the presence of SO 2 . Herein, we achieve enhanced low-temperature SO 2 -tolerant NO x reduction by manipulating the dynamic coordination environment of active sites. Engineered by coordination chemistry, SiO 2 -CeO 2 composite oxides with a short-range ordered Ce–O–Si structure were elaborately constructed on a TiO 2 support. A dynamic coordination environment of active sites is demonstrated from a Ce–O–Si local structure to a low-coordinated Ce-SO 4 2– species in the presence of SO 2 . The low-coordinated Ce-SO 4 2– species as new active sites maintain a high NO removal efficiency by preserving the good adsorption and activation capacity of NO and NH 3 reactants. This work proposes a new notion to improve the SO 2 resistance of catalysts by regulating the coordination environment of sulfated active sites, which is of significance for SO 2 -tolerant environmental catalysis in practical applications.