Oxides in silver–graphene nanocomposites: electrochemical signatures and electrocatalytic implications

Abstract

Herein we report an electrochemical approach to establish the presence of silver oxides in silver-reduced graphene oxide (Ag-rGO) nanocomposites synthesised under alkaline conditions. The recorded electrochemical signatures, further supported and validated by UV-Vis spectroscopy, XRD and TEM analysis, clearly establish the presence of an oxide phase of silver in the nanodimensional silver present in Ag-rGO. The Ag-rGO was tested for its electrocatalytic and electrosensing activity for hydroquinone (H₂Q) and ascorbic acid (AA). The presented results establish that the electrocatalytic and electrosensing potential of the Ag-rGO for H₂Q and AA can be enhanced through electroreduction of the oxide phase of silver in these nanocomposites. Our results prove that the electrocatalytic and electroanalytic activities of electroreduced Ag-rGO for AA are better than most of the electrode materials reported so far in the literature.