The electrical conductivity and the catalytic activity of SnO2 loaded TiO2 (anatase) particles were investigated in operando conditions. SnO2 depositions over commercial TiO2 samples (Sigma Aldrich and Rhone Poulenc) were obtained by the impregnation method. The samples were characterized by XRD, SEM/EDX and BET–N2 adsorption techniques. The AC electrical conductivity of the samples were measured between 25 and 400 °C under various atmospheres. The effect of the reactant mixture on the electrical conductivity and the catalytic performances of the samples were tested in propene oxidation. The results showed that the conductivity of SnO2/TiO2 samples depends strongly on the surface area of TiO2 support. The reducing effect of propene is more evident for higher surface area catalysts, these one showing also higher activity. On the other hand, the SnO2 deposition results in an increase of catalytic performances.
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