Photodegradation of 2-propanol in gas phase over zirconium doped TiO2: Effect of Zr content

The photocatalytic activity in the 2-propanol degradation, under UV and sunlight (SL)-type irradiations, of a series of Zr-TiO2materials, prepared using the sol–gel method, with a Zr content ranging from 0.25 to 1 wt%, was evaluated in this work. The physicochemical properties of the solids were characterized using X-ray diffraction, BET and porosity measurements, IR, UV–vis, Photoluminescence and X-ray photoelectron spectroscopy. The XRD data showed that the TiO2 was stabilized as anatase phase in all the samples and that the incorporation of Zr4+ into TiO2 lattice has led to a decrease of the crystallite size. The BET analysis confirmed that the addition of zirconium onto TiO2 support affected the surface area which increases with the increase of Zr4+ content. The UV-DRS spectra showed that, the incorporation of zirconium into TiO2 lattice leads to a slight decrease of the band gap energy of TiO2. The results of the photocatalytic test showed an enhancement on the photocatalytic activity of TiO2, in the 2 propanol degradation, by the doping with a low amount of zirconium. All the samples were found more active under UV illumination than under SL. In all cases, the highest efficiency in the 2-propanol photodegradation was observed for the 0.5% Zr-TiO2 sample and was essentially related to its lowest optical band gap energy.