Effective Nitric Oxide Reduction Over Core-Shell Cu-SSZ-13@meso-MO Catalysts with Significant Catalytic Activity and Hydrothermal Stability.

In this study, Cu-SSZ-13 zeolites are successfully coated with mesoporous metal oxides (CeO , Fe O , TiO and SiO ) and prepared as core-shell Cu-SSZ-13@meso-MO samples with hierarchical pore structure. Compared with Cu-SSZ-13, the catalytic activity and hydrothermal stability of the Cu-SSZ-13@meso-MO have been greatly improved. The promoting effect of meso-MO shell on the catalytic activity of Cu-SSZ-13 is mainly attribute to the presence of both microporous and mesoporous structures, the formation of more active isolated Cu ions and more L-acid sites, and the synergistic effect between Cu-SSZ-13 and meso-MO interaction. Moreover, all the Cu-SSZ-13@meso-MO catalysts maintain their activities to a greater extent after hydrothermal aging. The core-shell structure may play a protective role and greatly improve the hydrothermal stability of Cu-SSZ-13. More L-acidic sites and more isolated Cu ions are preserved under the protection of mesoporous structure.