Synthesis by sol–gel process, characterization and catalytic activity of vanadia–silica mixed oxides

This paper describes a new route for the preparation of V2O5–SiO2 mixed oxides with high vanadium content and high surface area by the sol–gel processing method. Dry samples were characterized by powder X-ray diffraction, electron paramagnetic resonance, Fourier-transform infrared, and energy dispersive X-ray spectrometry. Our results show that the incorporation of vanadium pentoxide into the silica matrix was obtained by intimate mixing of the two different inorganic polymers (Si–O and V–O based polymers), and the overall structure is held together by a Si–O–Si network interpenetrated with V–O–V polymeric chains. The catalytic activity of the V2O5–SiO2 mixed oxides was evaluated in the oxidation of the cyclooctene and styrene in liquid phase.