Determination of Enhanced Photocatalytic Activity of Silver Doped ZnO for Degradation of Rhodamine 6G

In this study, an attempt has been made to study the photocatalytic degradation of R6G in aqueous solution under visible light irradiation by using Ag doped ZnO. Silver ion doping is done by liquid impregnation method. Rhodamine 6G (R6G) is a basic dye used to dye wool, cotton, silk and paper where brilliant shades of fluorescent effects are required. But the release of this complex dye and its products in to the environment is hazardous. ZnO was doped with Ag of varying concentrations such as 0.5, 1.0, 1.5 atom percentages by liquid impregnation method in order to improve its photocatalytic activity and the samples were calcined at various temperatures for 2 h. The catalyst was characterized by XRD and SEM. The XRD patterns indicates well indexed phases of ZnO wurtize structure with no shift in peak positions and SEM images shows that the particles are in different shapes and sizes. Band gaps of ZnO and silver doped ZnO were calculated from UV-Visible Diffuse Reflectance Spectroscopic studies. The band gap energy of pure ZnO was found to be 3.28 eV and is slightly decreased to 3.27 eV for 1.0 atom% Ag-ZnO and remains unaffected for 0.5 and 1.5 atom% Ag-ZnO. The photocatalytic activity of ZnO was found to be enhanced by Ag doping. The dye degradation was investigated at different initial dye concentrations and photocatalyst doses.