Synthesis and Characterization of rGO/Fe₃O₄/SnO₂ Nanocomposite to Remove Terasil Black Dye from Aqueous Solutions

This study presents the synthesis and characterization of a ternary nanocomposite composed of reduced graphene oxide (rGO), magnetite (Fe₃O₄), and tin dioxide (SnO₂) nanoparticles (NPs), aiming at its application for the removal of Terasil Black dye from aqueous solutions, with specific relevance to textile industries. The nanocomposite fabrication involved a co precipitation technique followed by physical bonding with SnO2 NPs. Structural properties, surface morphology, and elemental composition were assessed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray (EDX) analysis. XRD analysis confirmed the formation of an amorphous phase with discernible diffraction peaks corresponding to specific lattice planes. FESEM images depicted irregular particle shapes and notable agglomeration. EDX analysis corroborated the presence of constituent elements. The adsorption isotherms, which exhibit (S) patterns as classified by Giles, indicate that the dye ions are arranged in a vertical orientation with respect to the surface of the nanocomposite. The adsorption process is described as endothermic and mostly influenced by physical interactions, which become more pronounced at elevated temperatures. The examination of the adsorption data reveals that the process is better described by the Freundlich isotherm model, indicating a surface that is not uniform in nature. This model signifies that both chemical and physical adsorption processes play a role, with their individual contributions varying at various temperature intervals. The results provide useful information on the thermodynamics and kinetics of dye adsorption on rGO/Fe₃O₄/SnO₂ nanocomposites. This information is crucial for optimizing the use of these nanocomposites in wastewater treatment.