Novel CuO@TiO2 Core–Shell Nanostructure Catalyst for Selective Catalytic Reduction of NOx with NH3

Abstract

CuO@TiO2 core–shell nanostructure catalyst with CuO core and TiO2 shell was prepared by a two-step method and then used in NH3-SCR reaction. FE-SEM, TEM and element mapping were used to investigate the morphologies of the sample. Their results indicated CuO nanorods were coated with TiO2 and thus forming a core–shell nanostructure. According to the results of N2 adsorption–desorption, XRD, Raman, XPS, NH3-TPD, H2-TPR and in situ DRIFTS, the core–shell nanostructure would benefit the formation of better redox ability, more oxygen vacancies, more acid sites and abundant adsorbed NOx species on the catalyst. Thus, the core–shell nanostructure catalyst presented significantly higher activity than pure CuO and TiO2. NH3-SCR reaction on CuO@TiO2 core–shell catalyst should follow both Eley–Rideal (E-R) mechanism and Langmuir-Hinshewood (L–H) mechanism. These findings may promote the development of the new effective non-vanadium-based SCR catalysts.