Biogenic silver nanoparticles using Schleichera oleosa leaf extract: nonlinear optical applications

Abstract

This work reports the biosynthesis of silver nanoparticles (Ag NPs) using Schleichera oleosa leaf extract and its nonlinear optical (NLO) properties. UV–Visible absorption spectroscopy confirmed the formation of Ag NPs with a characteristic surface plasmon resonance peak at 416 nm. X–ray diffraction studies revealed their crystalline nature, while transmission electron microscopy showed uniform spherical nanoparticles with an average size of 27.7 nm. FTIR analysis identified biomolecules in Schleichera oleosa leaf extract responsible for reducing and capping the nanoparticles. The nonlinear optical response is evaluated using the open–aperture Z–scan technique under nanosecond laser excitation at 532 nm. At lower excitation energies, the nanoparticles display saturable absorption, which switches to reverse saturable absorption at higher excitation energies. These findings underscore the potential use of green–synthesized Ag NPs in optical limiting and optical switching applications.