Structural study of titanium-doped vanadia and vanadium-doped titania catalysts

摘要

The morphologies and structures of nanostructurally assembled V_2O_5 doped with Ti as well as of th inverse system,V-doped TiO_2,have been studied using transmission electron microscopy and Raman spectroscopy.The bulk structure of the Ti-doped vanadia particles was found to be crystallized ina rod-like shape and to have he phase composition of V_2O_5 with titanium atoms nonuniformly distributed over the surface.A coherent interface between supported V_2O_5 and TiO_2 particles was found to be the main structural peculiarity of the inverse system,V-doped TiO_2 (anatase).The vanadium atoms are partially exchanged for titanium atoms at the interface,which leads to a change in the bond lengths of V=O and V-O-Ti in comparison with those observed in the monolayer supported vanadia catalysts.both materials showed good catalytic behavior in the reaction of selective reduction of NO by NH_3.