Preparation and Physicochemical Properties Studies of SnS₂ and SnS/SnS₂ Nanoparticles and use as Efficient Photocatalysts for the Degradation of Rhodamine B

The accumulation of dyes in water and their harmful effects on the ecological environment have attracted great attention worldwide. There is an urgent need to develop a method for rapidly and effectively degrading organic dyes. In the present study, effective SnS₂ and SnS/SnS₂ nanoparticles (NPs) have been synthesized by the conventional sol–gel method using two different solvents: hexane and triethylamine. The nanoparticles of SnS₂ and SnS/SnS₂ NPs were characterized by X-ray diffraction (DRX), Raman spectroscopy, thermal gravimetric (TGA), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), UV–Visible spectrometer (UV–Vis), photoluminescence (PL) and Zeta potential (ZP). DRX and Raman spectroscopy results confirmed the formation of two phases of tin sulfide such as SnS/SnS₂ for the sample synthesized with triethylamine solvent and SnS₂ in the case of hexane as a solvent. The SEM images showed the formation of cubic particles for SnS/SnS₂ and spherical particles for SnS₂. The photocatalytic activity of tin sulfide NPs was examined by the degradation of Rhodamine B (RhB) under UV irradiation and sunlight with the variation of dye concentration. Therefore, the photo-degradation efficiencies decreased with the increase in the concentration of dye. In all cases, SnS₂ has a higher degradation percentage (85%) and a higher degradation rate constant (K = 0.015 min⁻¹) than SnS/ SnS₂ (68%) and (K = 0.01 min⁻¹) under UV irradiation. For degradation under sunlight, where the degradation rate for SnS₂ is 84% (K = 0.016 min⁻¹ and the SnS/SnS₂ sample is 83% (K = 0.015 min⁻¹). As a result of this study, tin sulfide presents a potential future use compared to some oxides for the degradation of various organic pollutants to be suggested processing used in the wastewater treatment textile industry.