Sustainable synthesis of silver decorated graphene nanocomposite with potential antioxidant and antibacterial properties

In the pursuit of graphene-silver nanocomposites, Kigelia Africana stem extract was utilized for the sustainable synthesis of reduced graphene oxide-silver (KARG-Ag) nanocomposite. The UV-Visible spectra exhibited both graphene and Ag peaks at lambda(max) of 268 and 406 nm respectively, Raman spectra exhibited both D and G bands with an I-D/I-G ratio of 1.21. The XRD spectra showed the graphene peak at 2 theta = 26 degrees along with Ag peaks with an average particle size of 21.3 nm. Well stabilized Ag nanoparticles deposited on the transparent KARG sheets were further identified by TEM analysis. Thus, all the spectroscopic techniques proved the synthesis of said nanocomposite. The KARG-Ag nanocomposite (500 mu g/mL) showed superior total antioxidant activity (TAA-136) than the standard ascorbic acid (100) or KARG (82) and potential antibacterial activity against four different strains. Hence, the present green method and the potential applications of KARG-Ag nanocomposite may find environmental and clinical applications.