Enhanced sunlight-driven photocatalytic performance of Ag–ZnO hybrid nanoflowers

Photocatalytic materials such as Ag-coated ZnO nanoflowers, pristine ZnO nanoflowers and ZnO nanorods were synthesized by template-assisted method for the treatment of industrial waste water through photocatalysis. Electropolishing and anodization lead to the formation of alumina template. After that, hydrothermal treatment was carried out for the growth of ZnO nanoflowers and nanorods on the template. The morphology of synthesized samples was investigated by scanning electron microscope, X-ray diffraction patterns and energy-dispersive X-ray spectroscopy. XRD patterns of samples clearly indicate the well crystalline structure of synthesized materials. The presence of Ag in Ag-coated ZnO nanoflowers was confirmed by EDS spectral analysis and X-ray diffraction patterns. Grain size was found to be in the range of 10–25 nm as calculated by Scherer’s formula from XRD patterns. The sunlight-driven photocatalytic activity of Ag-coated ZnO nanoflowers, ZnO nanoflowers and ZnO nanorods was investigated and compared with each other. In addition, the stability and recovery of photocatalyst were also checked. Photocatalytic degradation experiment results indicated that Ag-coated ZnO nanoflowers had highest photocatalytic activity towards methylene blue dye.