Phytochemical preparation of Zinc Stannate nanoparticles by using lemon and grapefruit peels for removal of cadmium ions

The synthesis of Zinc Stannate (Zn2SnO4) nanoparticles may be achieved by utilizing lemon and grapefruit peels, as indicated by the results of this study. This analysis outlines a sustainable, cost-effective, and readily available approach. The Zn2SnO4 nanoparticles were generated biologically and were discovered to have a cubic crystalline structure, as established by structural analysis using Rietveld refinement. TEM microstructural examinations revealed that Zn2SnO4 nanoparticles exhibit a homogeneous distribution and possess an average diameter of around 21 nm. The Zn2SnO4 nanoparticles have an optical energy band gap of 3.05 eV and demonstrate a UV region peak, which showed that Zn2SnO4 nanoparticles were being formed. More precisely, the pH of the solution greatly affects the absorption of Cd2+ ions. Kinetic analysis involves the use of two types of models: pseudo-first-order and pseudo-second-order. The previous model yields an R2 value of 0.9031 and a rate constant (k1) of 0.41×10-2 min-1. However, the pseudo-second-order model provides a better match, as seen by its very high R2 value of 0.9932 and rate constant (k2) value of 4.4×10-3 g.(mg.min)−1. In addition, isotherm modeling shows that the experimental data closely match the Freundlich isotherm model.