A high activity photocatalyst of hierarchical 3D flowerlike ZnO microspheres: synthesis, characterization and catalytic activity.

In this study, three-dimensional (3D) hierarchical flowerlike ZnO microspheres have been hydrothermally synthesized by means of two surfactants at 100 °C and characterized by XRD, SEM, TEM, TG, FT-IR and UV-Vis spectroscopies. The results show that the 3D flowerlike ZnO microspheres are composed of 2D nanosheets. A possible formation mechanism is proposed: 0D Zn(5)(CO(3))(2)(OH)(6) colloids tend to form 2D nanosheets with the aid of sodium dodecyl sulfonic, and then, these nanosheets can assemble to 3D flowerlike microspheres by means of two surfactants of sodium dodecyl sulfonic and PEG 600. The flowerlike ZnO has low bandgap energy and exhibits high catalytic activity for photocatalytic degradation of Rhodamin B, which is attributed to its unique morphology and uniform hierarchical structure that significantly facilitates the diffusion and mass transportation of organic molecules and oxygen species in the degradation reaction.