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New V2O5-MoO3-TiO2-SO42- nanostructured aerogel system, containing V and Mo amounts representative of V2O5-MoO3/TiO2 commercial SCR catalyst, was developed via the one step sol gel method combined to supercritical drying approach...

New mesoporous and well-structured aerogel catalysts (CeO 2 -TiO 2 , WO 3 -TiO 2 and WO 3 -CeO 2 -TiO 2 ) were elaborated via the sol gel method, characterized by means of various techniques (XRD; N 2 -Physisorption at 77 K; NH 3 -TPD; H 2 -TPR; DRUV-Vis spectroscopy) and evaluated in the selective catalytic reduction (SCR) of NO by NH 3 . The results reveal that all the aerogel catalysts develop essentially the diffraction peaks of TiO 2 anatase phase and are classified as mesoporous materials with a high surface area (70 < S BET < 106 m 2 /g), large porosity (0.27 < V PT < 0.46 cm 3 /g) and nanometer size of crystallites (8-15 nmm). The addition of Ce and/or W influences differently the structure, texture, crystallites size, surface oxygen concentration, total acidity and redox ability of aerogel samples and clearly affects their NO-SCR activity which follows this order: TiO 2 < WO 3 -TiO 2 < CeO 2 -TiO 2 < WO 3 -CeO 2 -TiO 2 . It was also found that cerium species are more active in the low temperature NO-SCR reaction than tungsten ones (NO conversions obtained at 300 °C using CeO 2 -TiO 2 and WO 3 -TiO 2 were 75 % and 0 %, respectively). On the other hand, it was suggested that the interactions between Ce and W species play a key role in improving the reactivity of WO 3 -CeO 2 -TiO 2 catalyst in the SCR of NO by NH 3 . Interestingly, the NO conversion into N 2 reaches 85 % at 300 °C and exceeds 90 % between 320 and 400 °C over this novel meso-structured aerogel catalyst.