In situ preparation of mesoporous Fe/TiO2 catalyst using Pluronic F127-assisted sol-gel process for mid-temperature NH3 selective catalytic reduction

An Fe/TiO2 catalyst with uniform mesopores was synthesized using Pluronic F127 as a structure-directing agent. This catalyst was used for selective catalytic reduction of NO with NH3. The catalytic activity and resistance to H2O and SO2 of Fe/TiO2 prepared by a template method were better than those of catalysts synthesized using impregnation and coprecipitation. The samples were characterized using N2-physisorption, transmission electron microscopy, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, and in situ diffuse reflectance infrared Fourier-transform spectroscopy. The results showed that Pluronic F127 acted as a structural and chemical promoter; it not only promoted the formation of a uniform mesoporous structure, leading to a higher surface area, but also improved dispersion of the active phase. In addition, the larger number of Lewis acidic sites, indicated by the presence of coordinated NH3 species (1188 cm−1) and the N–H stretching modes of coordinated NH3 (3242 and 3388 cm−1), were beneficial to mid-temperature selective catalytic reduction reactions.