Photodegradation of Congo Red in Aqueous Solution on ZnO as an Alternative Catalyst to TiO2

In this research, the efficiency of ZnO and TiO2 was compared by photocatalytic degradation of Congo red azo dye. The effects of some parameters such as pH, dye concentration and irradiation time on the degradation rate of dye solution were also examined. In addition, the aggregation feature of Congo red was studied by using UV-Vis spectroscopy techniques. The recovery of the ZnO catalyst was also investigated