SnS_2/rGO: An Efficient Photocatalyst for the Complete Degradation of Organic Contaminants

摘要

Simple, efficient and visible light responsive reduced graphene oxide (rGO) loaded tin sulphide (SnS_2) photocat-alysts were prepared. Complete degradation of methyl orange (MO) was observed under visible light within the short span of time. Simple precipitation technique was followed for the synthesis of SnS_2 and rGO loaded SnS_2 photocatalysts. The as-synthesized SnS_2 based photocatalysts were characterized by X-ray diffraction studies (XRD), field emission-scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS) and UV-vis diffused reflectance spectroscopy (DRS). More importantly, the rGO addition considerably shifted the absorbance edge of SnS_2 from 605 nm (2.05 eV) to 576 nm (2.15 eV). Furthermore, rGO loading augmented the photocatalytic performance of SnS_2 by preventing the photoexcited electron-hole pair recombination. Very interestingly, more than 2.4 fold enhancement in photocatalytic activity was noticed by the loading of rGO to the SnS_2 photocatalyst. Different rGO loaded photocatalysts were examined and 4 wt% rGO loaded SnS_2 photocatalyst showed maximum degradation efficiency. Excess loading of rGO retarded the absorption behavior of SnS_2 in the visible light region as evident by the UV-vis absorbance spectra.