Nano ZnO microsphere/graphene photocatalyst and preparation method thereof

The invention belongs to the field of photocatalysis and relates to a nano ZnO microsphere/graphene photocatalyst and a preparation method of the nano ZnO microsphere/graphene photocatalyst. The photocatalyst disclosed by the invention is a nano composite photocatalyst formed by wrapping the surface of a nano ZnO microsphere with graphene. The photocatalyst is characterized in that the nano ZnO microsphere is prepared by a solution backflow method, is waxberry-shaped and consists of small crystals with hexagonal wurtzite structures, and the diameter of the nano ZnO microsphere is about 100-400nm. The nano ZnO microsphere/graphene photocatalyst is prepared by vacuum freeze-drying, thermal reducing and the like, and the process is simple and feasible. By virtue of the introduction of the graphene, the adsorption to organic molecules is enhanced, the spectral absorption range is expanded, and effective separation and transmission of photoproduction electron-hole pairs are promoted, so that ZnO/graphene achieves high photocatalysis efficiency in a methylene blue photocatalysis degrading process. According to the method, the steps are simple, and the cost is low; the obtained ZnO microsphere/graphene photocatalyst is high in catalytic activity, has a good photocatalysis effect and is desired to be applied to photocatalysis treatment on industrial pollutants.