Low temperature synthesis of plate-like BiOIs and their highly enhanced visible light photocatalytic performance

Abstract

A series of plate-like bismuth oxyhalides (BiOIs) with enhanced visible light photocatalytic properties was synthesized using a simple, template-free direct hydrolysis method. The as-prepared samples were characterized by X-ray powder diffraction (XRD) analysis, UV–vis diffuse reflectance spectroscopy (UV–vis DRS) and scanning electron microscope (SEM) imaging. In addition, the photocatalytic properties and mechanisms of the as-prepared samples were investigated by degrading methyl orange (MO) in an aqueous solution under visible light (λ>420nm). The results indicate that BiOI samples prepared in acidic solutions exhibit the highest photocatalytic activity and that the photocatalytic activities of all of BiOI samples exceeded P25. Furthermore, the photocatalyst was used for five cycles with the photocatalytic degradation efficiency remaining higher than 91.2%. Therefore, BiOIs are a promising visible light-induced photocatalyst for the treatment of chemically polluted water.