Enhanced Photocatalytic Activity of TiO₂-Coated NaY and HY Zeolites for the Degradation of Methylene Blue in Water

The TiO 2 -coated zeolite photocatalysts were prepared by dispersing zeolite powders in dilute titanium tetraisopropoxide solution. The characterization of the catalysts was carried out by X-ray diffraction, scanning electron microscopy, and N 2 adsorption. The presence of TiO 2 on zeolite surface was confirmed by UV−visible diffuse reflectance spectroscopy. The photocatalytic activity of TiO 2 -coated NaY and HY zeolite was investigated by degradation of aqueous solution of methylene blue dye. The highest photocatalytic activity was obtained with 1% TiO 2 -coated zeolite catalysts. This study demonstrated that the photocatalytic activity of TiO 2 -coated catalyst is higher than that of bare TiO 2 at a low amount of TiO 2 coating on the zeolite surface.