THE SYNTHESIS OF ZnBi2O4/x.0ZnS HETEROJUNCTION PHOTOCATALYSTS FOR PHOTODEGRADATION OF RHODAMINE B

Abstract

In the present work, highly visible-light active ZnBi₂O₄/x.0ZnS (x = 2, 6, 12, 24) heterojunction photocatalysts with various weight percentages of ZnS have been successfully synthesized by a simple co-precipitation. ZnBi₂O₄/x.0ZnS (x = 2, 6, 12, 24) heterojunction photocatalysts were characterized by X-ray diffraction, Fourier-transform infrared (FTIR), spectroscopy scanning electron microscopy (SEM) and UV-vis diffuse reflectance spectroscopy (UV-vis DRS). Their photocatalytic performances were evaluated by degrading Rhodamine B (RhB) in aqueous solution under visible light irradiation. The ZnBi₂O₄/x.0ZnS heterojunction photocatalyst containing 12% ZnS (ZnBi₂O₄/12.0ZnS) showed the best catalytic performance. More than 85,3% of Rhodamine B 40 mg/L solution was degraded after 90 min of visible light irradiation using ZnBi₂O₄/12.0ZnS at 1.0 g/L concentration. The photocatalytic experimental results were a good approximation to first-order kinetic behavior. Moreover, the ZnBi₂O₄/12.0ZnS catalyst showed good stability over four consecutive cycles.