Facile One-Pot Synthesis of Highly Stable Graphene-Ag0 Hybrid Nanostructures with Enhanced Optical Properties

We report a facile one-pot approach to synthesize graphene Ag-0 hybrid plasmonic nanostructures exhibiting superior optical properties. The Ag nanoparticles (NPs) (average particle size approximate to 25 nm) are found to be highly stabilized within the graphene matrix probably due to the favorable d-pi interaction among the vacant d-orbitals of Ag-0 and the pi-relectrons cloud of graphene moiety. Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES) have been performed to characterize the hybrid nanostructures. The synergistic effect of plasmonic Ag and graphene in the hybrid nanostructures results enhanced Raman and photoluminescence (PL) in the visible wavelength (similar to 520 nm). The nonlinear absorption (NLA) property in the femtosecond regime has been studied for this hybrid nanostructure. It is also observed that the two-photon absorption (TPA) coefficient of this hybrid increases from 0.0127 to 0.0155 cm/GW when the pulse energy is increased from 77 to 170 GW/cm(2). The study demonstrates enhanced optical response in the graphene- metal nanocomposite, which appears attractive for applications in graphene-based advanced photonic devices.