Facile production of Ag-Co3O4/rGO nanocomposite and its enhanced photocatalytic and electrochemical activities for practical applications

In this study, authors produced Co3O4, Ag-Co3O4 nanoparticles and Ag-Co3O4/rGO nanocomposites through a facile, one-step and cost-effective hydrothermal route; and thoroughly analyzed these materials using a variety of complementary techniques, including XRD, SEM/TEM, XPS, FTIR, VSM, UV-Vis, PL, photocatalytic and electrochemical measurements. The formation of cubic spinel structure in Ag-Co3O4/rGO nanocomposite was investigated by X-ray diffraction. The estimated average crystalline size in case ofCo3O4, Ag-Co3O4, and AgCo3O4/rGO samples was found to be 11.2, 14.1 and 17.5 nm, respectively. As a comparison to Co3O4 and AgCo3O4 nanoparticles, the absorption edge of Ag-Co3O4/rGO nanocomposite was significantly shifted towards the visible region, and hence the band gap is narrowed due to highly conducting Ag and rGO incorporation. The photo-generated electrons and holes were rapidly transferred from Co3O4 to Ag and rGO, leading to reduced PL intensity ofAg-Co3O4/rGO nanocomposite. Authors evaluated the photocatalytic efficiency of synthesized AgCo3O4/rGO nanocomposite, which exhibited an enhanced photodegradation potential against RhB dye. Authors also examined the electrochemical activity of as-obtained Ag-Co3O4/rGO nanocomposite using cyclic voltammetry and galvanostatic charge-discharge cycle analysis, demonstrating its employability in supercapacitors as it possessed excellent specific capacitance.