Different exposed facets VOx/CeO2 catalysts for the selective catalytic reduction of NO with NH3

VOx/CeO2 catalysts, employing CeO2 nanocubes (NCs), nanorods (NRs), and nanopolyhedrons (NPs) with predominately exposed {1 0 0}, {1 1 0}, and {1 1 1} facets as the supports, were prepared by an incipient wetness impregnation method. The catalysts were used in the selective catalytic reduction (SCR) of NOx with NH3. The SCR performance showed that V-CeO2-NPs could achieve significantly higher NO conversion than V-CeO2-NCs and V-CeO2-NRs in the entire temperature range. The characterization results confirmed that the redox and acidic properties of VOx/CeO2 catalysts were closely related to the exposed facets of the CeO2 supports. The excellent SCR activity of V-CeO2-NPs should be attributed to its appropriate redox ability and abundant surface acid sites, which are associated with the predominately exposed {1 1 1} facets of CeO2-NPs.