PHYTOGENIC SYNTHESIS, OPTICAL, FUNCTIONAL, STRUCTURAL, AND THERMAL PROPERTIES OFEnicostemaaxillare-MEDIATED SILVER NANOPARTICLES

Abstract

The present study investigates the green synthesis of silver nanoparticles (AgNPs) using an aqueous leaf extract of Enicostema axillare as a biological reducing and stabilising agent. Fresh leaves of E. axillare were collectedandprocessed into AgNPs using a green chemistry approach. The as-synthesised silver nanoparticles were studied usingUltraviolet-visible spectroscopy (UV), Fourier transform infrared spectroscopy (FTIR), X-Ray Diffraction (XRD), Energy-Dispersive X-ray spectrophotometer (EDX), Thermogravimetric analysis (TGA), and Field EmissionScanning Electron Microscopy (FESEM). XRD analysis shows a clearly defined hkl peaks of (111), (200), (211), (220), (221) and (311) of face-centred cubic silver, with crystallite sizes of about 40 - 70 nm estimated usingtheScherrer equation. TGA shows the thermal stability of the synthesised AgNPs with 22% total weight loss. Withthese findings, E. axillare leaf extract can be a very effective and environmentally friendly systemfor synthesisingstable AgNPs with nanoscale size and crystalline structure. Due to their stability, phytochemical cappingandabundant amount of silver, the AgNPs synthesised have a great potential of being used in diverse areas of biomedical, environmental and nanotechnological practices.