Simple and inexpensive synthesis of rGO-(Ag, Ni) nanocomposites via green methods

Abstract

In this study, we report the successful reduction of graphene oxide (GO) with cost effective and environment friendly methods. In the first method, we irradiated GO with highly energetic UV laser to obtain reduced GO (rGO). Moreover, Ag and Ni nanoparticles (NPs) were also productively deposited on rGO by in situ reduction of metal salts with ultraviolet (UV) laser irradiation. In the second method, we employed neem leaf extract as reducing agent to synthesise rGO decorated with Ag and Ni NPs in a one-step approach. The reduction of GO as well as the deposition of Ag and Ni NPs on rGO was examined by Raman spectroscopy. We also performed ultraviolet–visible (UV-vis) spectroscopy, X-ray diffraction and SEM analysis to observe absorption in UV-vis range, crystallographic orientations and surface morphology of rGO-NPs composites respectively. Both the reducing sources were found efficient for the reduction of GO and successful deposition of metal NPs on the surface of rGO via in situ reduction of metal salts. However, UV laser irradiation mediated reduction of GO was better relative to the neem leaf extract.

Keywords:

• Green method
• Photoreduction
• UV laser
• Reduced graphene oxide
• Nanocomposite
• Raman spectroscopy