The characterization and activity of F-doped vanadia/titania for the selective catalytic reduction of NO with NH 3 at low temperatures

Abstract

A F-doped vanadia/titania catalyst has been developed by partly substituting the lattice oxygen of the catalyst with fluorine, using NH 4F as a precursor. The aim of this novel design was to promote the activity of a catalyst with low vanadia loading in the low-temperature selective catalytic reduction of NO with NH 3. Analysis by N 2 physisorption, XPS, ICP, XRD, ESR and PL spectra showed that fluorine doping facilitated the formation of V 4+ and Ti 3+ ions mainly by charge compensation, promoted the distribution of vanadium on the catalyst surface, and increased the amount of surface superoxide ions. The catalytic activity of NO removal was promoted by F-doping. And the catalyst with [F]/[Ti] = 1.35 × 10 −2 showed the highest NO removal efficiency in SCR reaction at low temperatures.