SnS2/RGO based nanocomposite for efficient photocatalytic degradation of toxic industrial dyes under visible-light irradiation

The treatment of toxic organic effluents is highly desired for the preservation of clean air, soil, and water. Therefore, it is paramount to develop low cost, visible-light-driven photocatalysts with high absorption efficiency to degrade these toxic pollutants. This work reports the one-pot hydrothermal synthesis of mixture of tin disulfide (SnS2) quantum dots (QDs) and nanodiscs (NDs), supported on reduced graphene oxide (RGO) sheets based photocatalysts for degradation of toxic industrial dye, remazol brilliant red (RBR) and remazol brilliant blue (RBB) under visible light irradiation. The structure and morphology of the as-synthesized photocatalysts were studied exhaustively by X-ray diffraction analysis, field emission scanning electron microscopy, transmission electron microscopy, Fourier transforms infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis which confirmed the formation of NDs (∼21 nm), plates (long axis: ∼58.23 nm, thickness ∼4.65 nm) and QDs (size ∼ 3.6 nm) of SnS2 anchored onto RGO sheets. The composite of SnS2/RGO (BET surface area: ∼103.55 m2/g) showed improve photocatalytic dye degradation (∼99.7% and ∼97% for RBB and RBR dye) compare to pristine SnS2 (BET surface area: ∼71.09 m2/g) primarily due to support from RGO sheets, provided a facile path for excitation of electrons from the valence to conduction band. A reusability study, effect of solution pH, and the degradation behavior of colorless pollutant (to differentiate between direct and indirect photocatalysis) were performed to confirm the stability and the photocatalytic mechanism. From the comparative study, it can be postulated that SnS2/RGO nanocomposite is an efficient photocatalyst in the fields of solar energy conversion, wastewater treatment, and environmental remediation.