The shape effect of TiO2 in VOx/TiO2 catalysts for selective reduction of NO by NH3

Abstract

Anatase TiO₂ nanosheets exposing 74% of {001} facets and nanospindles exposing 81% of {101} facets were hydrothermally synthesized with the aid of F⁻ and CH₃COO⁻, respectively. Upon vanadia loading at a monolayer amount level, the {001} facets on TiO₂ nanosheets favored the deposition of octahedral vanadia species, but the {101} facets on TiO₂ nanospindles resulted in the formation of tetrahedral vanadia species. The shape effect of TiO₂, in terms of its predominantly exposed crystal facets, on the catalytic performance of VO_x/TiO₂ samples for selective reduction of NO with NH₃ was examined. The octahedral vanadia species on TiO₂ nanosheets showed a significantly higher activity than the tetrahedral vanadia species on TiO₂ nanospindles.