Novel CeO@TiO core-shell nanostructure catalyst for selective catalytic reduction of NOx with NH.

The CeO@TiO core-shell nanostructure catalyst prepared by a two-step hydrothermal method was used for selective catalytic reduction (SCR) of NOx with NH in this study. The catalyst presented the obvious core-shell structure, and the shell was amorphous TiO which could protect the active center from the SO erosion. The catalyst showed high activity and stability, excellent N selectivity and superior SO resistance and HO tolerance. Characterizations such as TEM, HR-TEM, XRD, BET, XPS, NH-TPD, and H-TPR were carried out. The results indicated that the catalyst had large surface area and the active sites were well dispersed on the surface. The NH-TPD, H-TPR and XPS results implied that its increased SCR activity might be due to the enhancement of NH chemisorption and the increase of active oxygen species, both of which were conductive to NH activation. The excellent catalytic performance suggests that it is a promising candidate for SCR catalyst.