Eco-friendly Fabrication of GoldNanoparticles: Evaluation of Catalytic DyeDegradation and Antimicrobial Potential

Abstract

Background: Plant-derived and agricultural wastes constitute a major portion of global solid waste. Valorization of such
biowastes offers a sustainable and eco-friendly approach for nanoparticle synthesis. Aim: This study aimed to green
synthesize gold nanoparticles (AuNPs) using pomelo peel extract (PPE) and evaluate their photocatalytic dye degradation
and antibacterial potential. Methodology: The AuNPs were bio-synthesized using optimal conditions (pH = 5, 1mM
AuCl3, 10mg PPE, and 80°C). The produced nanoparticles were identified through UV-Visible (UV-VIS) spectroscopy,
X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM),
and Atomic Force Microscopy (AFM). Photocatalytic efficiency was examined using Methyl Red, Rhodamine B, and
Quinoline Yellow in the presence of sunlight. Antibacterial effectiveness was tested using chosen Gram-positive and
Gram-negative bacteria. Results: The UV-vis spectrum displayed an SPR peak of 525-550 nm. Crystalline nature was
evidenced by X-ray diffraction of the planes (111), (200), and (220). Spherical polydisperse nanoparticles with 25-65
nm particle size were observed using SEM and AFM images. The presence of plant phytochemicals as reducers and
stabilizers for gold nanoparticles was inferred from FTIR analysis. The synthesized gold nanoparticles showed high
efficiency in dye degradation with percentage values of 84.78% (Methyl Red), 78.85% (Rhodamine B), and 82.16%
(Quinoline Yellow) within 240 minutes, following pseudo first order kinetics. The synthesized AuNPs showed dose.
Conclusion: The study demonstrates an eco-friendly and efficient approach for synthesizing AuNPs using pomelo peel
waste, with promising applications in wastewater treatment and antibacterial therapy.