Highly efficient light responsive BiOCl/AgI composites for photocatalytic degradation of 3-CP under visible and UV light irradiations

Abstract

Novel visible light sensitive BiOCl/AgI composites were synthesized by a facile precipitation technique. Samples were characterized by SEM (scanning electron microscope), XRD (X-ray diffraction), UV-DRS (UV-diffuse reflectance spectroscopy) and XPS (X-ray photoelectron spectroscopy). Photocatalytic activity of the samples was evaluated using 3-CP under UV-Visible irradiation. Compared to pure BiOCl, AgI and other BiOCl/AgI, the composites exhibited more catalytic activity under both UV and visible lights within 120 min. Optimal content of the BiOCl in the composite system was found as 40%. The excellent degradation of 3-CP under light was attributed to the efficient separation of photo-induced charge carriers, defect levels, iodide and chlorine radicals. The radical scavenging activities also illustrate that holes and superoxide radicals are dominant agents in the photocatalytic degradation process. These results demonstrated that BiOCl/AgI systems are very useful to decompose persistent organic pollutants.