Gripe water-mediated green synthesis of silver nanoparticles and their applications in nonlinear optics and surface-enhanced Raman spectroscopy

In the present study, silver nanoparticles were synthesized from aqueous silver nitrate through a simple, eco-friendly and 'green' method using gripe water as reducing as well as stabilizing agent. Control over the dispersity of silver (Ag) nanoparticles was attained by altering the synthesis process. The size and morphology of the particles were perceived using high-resolution transmission electron microscope and the surface plasmon resonance of the prepared nanoparticles was observed by UV-IS spectrum. Herein, we report the nonlinear optical behavior and surface-enhanced Raman spectroscopy of silver nanoparticles with different particle size and dispersity. The nonlinear optical behavior was studied by single beam Z-scan technique using tunable Ti: Sapphire mode-locked femtosecond laser as source. The nonlinear optical parameters such as the nonlinear refractive index, nonlinear absorption coefficient beta and the third-order nonlinear susceptibility chi(3) of the prepared Ag nanoparticles were obtained for various wavelengths by tuning the wavelength of the laser from 700 to 950 nm. Surface-enhanced Raman spectroscopy (SERS) is an inspiring phenomenon especially in the case of silver nanoparticles. The as-synthesized silver nanoparticles show huge enhancements in the order of 10(9) in the Raman spectrum of rhodamine 6G dye.