DEPOSITED Bi2O3 THIN FILMS ON SINTERED SILICA FOR PHOTOCATALYTIC WATER TREATMENT

Bismuth oxide (Bi2O3) thin films were deposited on sintered silica surface by the spray pyrolysis method using bismuth acetate as the precursor salt. Spray pyrolysis enables uniform film distribution on sintered silica. The films were characterized by X-ray diffraction (XRD) to investigate the obtained Bi2O3 phase, UV-vis diffuse reflectance spectroscopy (DRS) to obtain the energy band gap, and Field Emission Scanning Electron Microscopy (FESEM) to study the morphological structure. XRD pattern revealed that obtained phase of films is tetragonal β- Bi2O3, by using DRS results the calculated energy band gap is 2.4eV and FESEM images show porous flowery structures. Furthermore the heterogeneous photocatalytic activity of the films was investigated by introducing the deposited silica filters into organic dyes solution and irradiating in UV and visible light for photocatalyst activation. Bi2O3 thin films shown good photocatalytic activity showing that (i) spray pyrolysis is a promising deposition method and that (ii) deposited silica filters are suitable support to promote effective interaction of photocatalyst with dye molecules while avoiding the problem of photocatalyst powders suspension in dye solution. Improved photocatalytic activity in visible light proves Bi2O3 thin films for sustainable water treatment and related applications.