Synthesis, Characterization, and Catalytic Applications of Silver Nanoparticles Prepared by Green Chemistry Methods

Abstract There is a rising interest towards sustainable nanomaterials and hence green synthesis methods of metallic nanoparticles. This work focuses on the synthesis, characterization, and catalytic applications of plant-based chemically prepared silver nanoparticles (AgNPs) synthesized by green chemistry methods using various reducing / stabilizing agents. The precursor salt was silver nitrate and the reducing medium was an aqueous plant extract. The formation of silver nanoparticles was initially observed by a distinct change in colour followed by ultraviolet-visible spectroscopy, which showed a characteristic surface plasmon resonance peak. These were characterized at structural and morphological levels using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and particle size analysis (PSA). The synthesized nanoparticles were mostly spherical with nanoscale size distribution and had crystalline nature. The involvement of phytochemicals in the reduction and stabilization processes was confirmed by functional group analysis. Green-synthesized silver nanoparticles were characteristically utilized for catalytic efficiency testing in terms of dye reduction or degradation of chosen organic pollutants in aqueous medium. The obtained results showed the catalytic efficiency of the nano systems, based on the shortened reaction time and increased degradation percentage compared to the control system. These results corroborate the feasibility of green synthesis as an inexpensive, eco-friendly, and straightforward way for the generation of catalytic active silver nanoparticles. The green synthesis of AgNPs via plant-extracts provides a significant advancement toward sustainable nanochemistry by showing its catalytic and environmental applications.