Beta-Cyclodextrin-triggered fabrication of broccoli-like ZnO nanoaggregates with enhanced photocatalytic capability
2020 World Scientific Publishing Company. Nanocrystallite aggregates have great potential in semiconductor-based photocatalysis toward environmental pollution removal. In this work, we reported the fabrication of broccoli-like zinc oxide nanoaggregates in the presence of beta-cyclodextrin in ethylene glycol-H2O medium. The composition and structure of the as-obtained ZnO nanoaggregates were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. It was observed that the beta-cyclodextrin played an important role in the fabrication of such broccoli-like structure. A plausible formation mechanism was discussed on the basis of the controllable experiments. The photocatalytic performance of the products was studied through the photodegradation of rhodamine B under simulated sunlight irradiation. Compared to the spherical ZnO nanoaggregates and ZnO broken spheres, the broccoli-like ZnO exhibited superior photocatalytic efficiency. Based on the photocurrent and electrochemical measurement results, the higher separation efficiency of the photogenerated carriers and lower recombination efficiency of the photoinduced electron-hole pairs over the broccoli-like ZnO nanoaggregates contributed to their remarkable photocatalytic activity.