Characterization of spherical Ag nanoparticles synthesized from the agricultural wastes of Garcinia mangostana and Nephelium lappaceum and their applications as a photo catalyzer and fluorescence quencher

Abstract

The present investigation reports a comparative study of direct Sunlight and UV irradiation driven silver nanoparticles (AgNPs) synthesized from water extracts of seasonal fruit wastes of Garcinia mangostana L. (fruit rind and seed), and Nephelium lappaceum L. (peel and seed). Synthesized NPs were characterized using Ultraviolet–Visible spectrophotometry, Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), and Energy-dispersive spectroscopy (EDX). As per the SEM and TEM images, synthesized NPs appeared to be spherical, with a UV absorbance range of 400–440 nm. FTIR spectra demonstrated peaks at 3268–3290 cm−1, 2347–2363 cm−1, 2099–2103 cm−1, and 1635–1639 cm−1 for fruit waste extracts, with low intensity for AgNPs. The particle size of AgNPs vary from 12.1–31.3 nm, as observed from the TEM, and the EDX spectra confirmed the purity of the AgNPs. The quenching ability of biogenic AgNPs was evaluated using Rhodamine B dye under Fluorescence spectrophotometry. As per the results, all biogenic AgNPs behaved as quenchers. The highest fluorescence quenching activity was observed in AgNPs synthesized via G. mangostana peel extract and N. lappaceum seed extract. The photocatalytic activity of the NPs was measured by the degradation of Methylene Blue dye under Sunlight. Among all four, AgNPs synthesized via N. lappaceum seed extract act as an effective photocatalyst, and the degradation efficiency was recorded as 95% with 22 min of Half-life. Thus, this study proposes that the synthesized biogenic AgNPs behave as an ideal material for dye degradation and fluorescence quenching.