Characterization and Efficacy of Silver Nanoparticles Synthesized from Fruit Waste Extracts for Heavy Metal Remediation

This work focuses on the green synthesis and characterisation of silver NPs (AgNPs) with fruit peel extract as a sustainable reducing and stabilizing agent. Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy – energy dispersive X-ray spectroscopy (FESEM-EDS) and ultraviolet-visible (UV-V’is) spectroscopy were used to validate the successful biosynthesis of AgNPs. The FTIR evaluation indicated substantial alterations in functional groups, including the O-H peak changing from 3184 cm⁻¹ to 3299 cm⁻¹ and the C=O peak from 1771 cm⁻¹ to 1636 cm⁻¹, demonstrating the involvement of polyphenols and carbonyl groups in Ag⁺ reduction and their stabilization. A fresh Ag-O bond signal at 588 cm⁻¹ confirmed the production of AgNPs. XRD studies showed their crystalline structure, while FESEM-EDS revealed their spherical form and elemental content. UV-V’is spectroscopy confirmed the production of AgNPs with a distinct Surface Plasmon Resonance (SPR) peak. Pb(II), Cr(VI) and Cd(II) were all effectively removed by biosynthesized AgNPs; their ideal adsorption pH ranges were 6–8, 3–4, and 8–9, respectively. Pb had the strongest attraction, and maximum removal efficiencies were attained at low concentrations and increasing adsorbent dosages. AgNPs provide a long-term option for heavy metal cleanup, especially the elimination of lead. This study demonstrates the efficient utilization of fruit peel waste for green synthesis of AgNPs, providing a cost-effective and environmentally friendly technique that adheres to green chemistry principles and has potential uses in environmental remediation.