Decolorization of crystal violet using nano-sized novel fluorite structure Ga2Zr2-xWxO7 photocatalyst under visible light irradiation

Fluorite type Zr based oxides with the composition Ga2Zr2-xWxO7 (x=0, 0.05, 0.1 and 0.15) were prepared using the citrate technique. Appropriate characterizations for all prepared materials were carried out. XRD clarified that all the undoped and W doped Ga2Zr2O7 samples were crystallized in the cubic fluorite phase structure. The average particle size of the prepared samples was in the range (3-8 nm). The lowest band gap (1.7 eV) and the highest surface area (124.3 m2/g) were recorded for Ga2Zr0.85W0.15O7. The Photocatalytic impacts of the prepared systems were studied by removal of crystal violet dye (CV) employing visible illumination taking in consideration initial dye concentrations, duration of visible irradiation treatment, catalysts dose and the dopant concentration. The obtained results showed faster dye removal with the boost of the catalyst dosage. W doping shifted the absorption to the visible light range by decreasing the band gap from 4.95 eV for parent Ga2Zr2O7 to 1.7 eV ...