Photocatalytic Activity of TiO_(2)-WO_(3) Composites

摘要

TiO_(2)-WO_(3) photocatalysts were prepared in a vacuum evaporator by impregnation of TiO_(2) with WO_(2) dissolved in an H_(2)O_(2) solution (30percent) and followed by calcination at 400 and 600 deg C. XRD analyses showed that at 400 deg C monoclinic phase of WO_(3) was dominated whereas at 600 deg C both monoclinic and regular phases of WO_(3) were present. Modification of TiO_(2) by WO_(3) caused increasing in the absorption of light to the visible range. TiO_(2) and photocatalysts modified with low amount of WO_(3) (1-5 wt. percent) showed high adsorption of Acid Red (AR) on their surface and enhanced photocatalytic activity under UV irradiation. Under visible light irradiation, TiO_(2)-WO_(3) photocatalysts prepared at 400 deg C were more active for AR decomposition than those prepared at 600 deg C suggesting that monoclinic phase of WO_(3) is more active under visible light than regular WO_(3). Although TiO_(2)-WO_(3) photocatalysts appeared to be active under visible light for decomposition of AR, the UV irradiation was more efficient.