Photocatalytic decomposition of acetone over dc-magnetron sputtering supported vanadia/TiO2 catalysts

Two series of titania-based photocatalysts were prepared by the sputtering method, in pure Ar atmosphere at a pressure of 0.5 Pa using a vanadium target source in a direct dc mode with a discharge of 300 V. The time of deposition was varied between 1 and 10 min in order to obtain different thickness of vanadium films. The first catalysts series (samples V/TiO2(A)-n) was prepared deposing vanadium Oil pure TiO2 anatase, while for the second series (samples V/TiO2(AR)-n) the deposition was made onto TiO2 Degussa P25. The samples have been investigated by means of vibrational (DRIFT and Raman) and optical (UV-vis in the DRS mode). Chemical analysis of the samples was made using the ICP-AES technique, while the crystalline structure of the deposed films onto the TiO2 supports was checked by X-ray diffraction (XRD). The samples morphology was analyzed using the AFM microscopy. The photocatalytic decomposition of acetone was considered as a reaction test. The activity of the investigated catalysts was found to be influenced by both the amount of vanadium and the Support nature. Among the investigated catalysts V/TiO2(AR)-32 nm exhibited the higher activity. The activity of this catalyst was also superior to that of TiO2 Degussa P25. (C) 2008 Elsevier B.V. All rights reserved.