Fabrication of BiOI Hierarchical Microspheres with Efficient Photocatalysis for Methylene Blue and Phenol Removal

BiOI hierarchical microspheres were synthesized by a solvothermal method. The different ratio of the amount of substance (Bi:I) drastically affects the feature that is embodied in multiaspect, such as crystallinity, morphological characteristics, component content, specific surface area and band gap width. These dissimilarities exert a great influence on photocatalytic performance. Ethylene glycol acts as soft template to guide the generation of the hierarchical microspheres. The presence of methanol has a positive effect on uniformity of reaction system in physical and chemical properties, because of its easy dispersibility and intersolubility. With interaction of mixed solvent, it leads to generate the uniform microspheres. The as‐received samples are characterized by X‐ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), energy dispersive spectroscopy(EDS), N 2 adsorption‐desorption, UV–vis diffuse reflectance spectroscopy (DRS), X‐ray photoelectron spectroscopy (XPS), and fluorescence spectrophotometer. The formation of BiOI hierarchical microspheres were discussed with variational ratio of the amount of substance in mixed alcohol. To evaluate photocatalysis of as‐prepared BiOI, the methylene blue and phenol were exposed to visible light, which indicated degradation efficiency up to 98.09% just in 50 min and 94.14% within 6 h. The result shows that BiOI hierarchical microsphere is a promising photocatalyst in practical application.