Facile preparation of BiOCl x I1−x composites with enhanced visible-light photocatalytic activity

Abstract

BiOCl x I1−x composites demonstrating enhanced visible-light photodegradation activity were prepared via a hydrothermal method. The as-prepared samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, UV–Vis diffuse reflection spectroscopy, field emission scanning electron microscopy, fourier transform infrared spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller, and electrochemical impedance spectroscopy, to demonstrate the successful formation of heterojunction in BiOCl x I1−x . When BiOI content was 50% (x = 0.5), BiOCl0.5I0.5 showed an absorption edge of up to 560 nm, a bandgap energy (E g) of 2.21 eV, and an obvious red shift by approximately 190 nm compared with bare BiOCl. In contrast with pure BiOCl that shows nearly no photocatalytic activity, the BiOCl x I1−x hybrid photocatalyst exhibited higher enhanced visible-light photocatalytic activity for photodegradation of methylene blue. The superior photocatalytic activity of this hybrid photocatalyst is attributed to the large surface areas and pore volume, good oxidizing power and light utilization, and modified band structure resulting from the presence of BiOCl x I1−x heterostructure. This work could provide a facile method to obtain a BiOCl x I1−x visible-light photocatalyst and to enhance the photocatalytic performance of the catalyst for practical application, because this photocatalyst is low cost and can be easily scaled up.