The hydrothermal stability of Cu-ZSM-5 catalyst was enhanced after surface modification.
An inert silica layer was deposited on the surface of Cu-ZSM-5 and formed a protective layer.
The contact between Si and Cu and Al atoms could form Si-O-Al and Si- O<noscript>noscript>Cu bonds.
The redox and acidity properties of Cu-ZSM-5-CLD-Aged catalyst were largely retained.
The adsorption and activation of NO and NH3 was almost unchanged over Cu-ZSM-5-CLD catalyst before and after hydrothermal treatment.