Synthesis of ZnO/SrO nanocomposites for enhanced photocatalytic activity under visible light irradiation

To enhance the photocatalytic activity of zinc oxide (ZnO) nanostructures, strontium oxide (SrO) nanoparticles (NPs) have introduced into ZnO through a facile, inexpensive, one pot hydrothermal approach. The as prepared samples were extensively characterized using various techniques. The morphological analysis revealed, in the absence of Sr, ZnO nanoflowers consist of hexagonal nanorods. Addition of Sr in various amount has profound effect on the morphology. Initially, SrO nanoparticles were formed on the surface of ZnO nanorods. As the weight percentage of SrO increased, the morphology of SrO nanoparticles have been changed to bipods and tripods. The XRD studies revealed good crystallinity of samples with presence of both phases, ZnO as well as SrO, simultaneously. The photocatalytic degradation of ZnO/SrO nanocomposites were 9 times faster than the pure ZnO under visible light irradiation. The optimum Sr weight percentage was found to be 3%. Our experimental results revealed that photogenerated superoxide (O2−) radicals are the main reactive species for the degradation of MB. The maximum degradation efficiency was observed for 3% of Sr, the MB completely degrades after 6 min of irradiation.