Abstract

This study presents a green synthesis approach for silver nanoparticles (AgNPs) using aqueous leaf extract of Camellia sinensis as both a reducing and capping agent. The synthesized nanoparticles were comprehensively characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and UV-Visible spectroscopy.

XRD analysis confirmed the face-centered cubic (FCC) crystalline structure of AgNPs with an average crystallite size of 18.4 nm calculated via the Scherrer equation. FTIR spectra revealed the presence of functional groups from the plant extract acting as stabilizing agents. TEM imaging demonstrated uniform spherical morphology with particle sizes in the 10–30 nm range and narrow size distribution (PDI = 0.12).

UV-Vis spectroscopy showed a characteristic surface plasmon resonance (SPR) peak at 425 nm, confirming successful nanoparticle formation. The synthesized AgNPs exhibited high purity (99.2%) and excellent colloidal stability over 60 days at room temperature. These results demonstrate that green synthesis using plant extracts provides an environmentally benign, cost-effective route to produce stable, well-characterized silver nanoparticles suitable for downstream biomedical applications.