ZnS and ZnS/ZnO assembly for photocatalytic removal of Reactive Red 66

The current work investigated the effect of ZnS and ZnS/ZnO assembly on the photocatalytic removal of Reactive Red 66 from an aqueous solution. The photocatalytic activities were carried out using both UV irradiation and visible light, and the effects of various operating parameters, such as pH, catalyst loading, dye concentration, and contact time, were studied. The results showed that the ZnS/ZnO heterostructure exhibited a higher dye removal percentage than ZnS alone and assisted in the photodegradation of Reactive Red 66. Maximum adsorption was found at pH 2 and 5, indicating that the dye removal was strongly pH-dependent. The highest dye removal efficiency under UV light was 77.7 and 91.7% using ZnS and ZnS/ZnO, respectively. Furthermore, the degradation percentage of Reactive Red 66 by ZnS and ZnS/ZnO decreased to 43.3 and 75.2% under visible light. The enhanced photocatalytic activity of the ZnS/ZnO heterostructure is attributed to its high absorption of light, efficient separation of electron-hole pairs, and quick surface reaction in the heterostructure.