Assembled composite of hematite iron oxide on sponge-like BiOCl with enhanced photocatalytic activity

Abstract

Herein, sponge-like bismuthoxychloride (BiOCl) and hematite iron oxide (α-Fe2O3) were synthesized by simple and inexpensive method via two-step process, including hydrothermal and solution combustion method. The BiOCl/α-Fe2O3 composite photocatalysts were prepared by incorporating various weight ratios of α-Fe2O3 on BiOCl by a low-cost wet chemical process. The chemical interaction, phase and crystalline nature of the samples were ascertained by Fourier transform infrared spectroscopy (FT-IR) and x-ray diffraction (XRD). Further, the surface morphology and optical properties of the fabricated materials was characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis diffuse reflection spectroscopy (DRS). Photocatalytic activities of the fabricated samples towards the photocatalytic degradation of direct red 81 (DR81) was evaluated under ultraviolet light illumination. The BiOCl/α-Fe2O3 composites showed remarkably enhanced photo-induced catalytic performances. The photocatalyst with optimal content of α-Fe2O3 with the highest photocatalytic performance was observed to 1%-BiOCl/α-Fe2O3. The synergistic improvement in the photodegradation of BiOCl/α-Fe2O3 sample may be because of an expansion in the noticeable light absorption efficiency as well as fast photo-generated charge separation. A probable mechanism for the photocatalytic degradation has been proposed for the catalytic performance of BiOCl/α-Fe2O3 photocatalyst. Keywords: Bismuthoxychloride, Direct red 81, Iron oxide, Photocatalysis, Photodegradation