Sono-Chemical Synthesis of Silver Quantum Dots Immobilized on Exfoliated Graphitic Carbon Nitride Nanostructures Using Ginseng Extract for Photocatalytic Hydrogen Evolution, Dye Degradation, and Antimicrobial Studies.

Due to modernization and the scarcity of fossil fuel resources, energy demand is continuously increasing. In this regard, it is essential and necessary to create a renewable energy source that can meet future energy demands. Recently, the production of H by water splitting and removing pollutants from the water has been essential for issues of energy and environmental demands. Herein, g-CN and Ag-g-CN composite structures have been successfully fabricated by the ultrasonication method. The physio/photochemical properties of prepared g-CN and Ag-g-CN were examined with different analytical techniques such as FTIR, XRD, UV-DRS, SEM, TEM, PL, and XPS analyses. The silver quantum dots (QDS) anchored to g-CN structures performed the profound photocatalytic activities of H production, dye degradation, and antimicrobial activity under visible-light irradiation. The Ag/g-CN composite with an Ag loading of 0.02 mole has an optimum photoactivity at 335.40 μmol g h, which is superior to other Ag loading g-CN composites. The synthesized Ag/g-CN nanoparticles showed potential microbial inhibition activity during the preliminary screening, and the inhibition zones were comparable to the commercial antibiotic chloramphenicol. The loading of Ag into g-CN paves the suppression, recombination and transfer of photo-generated electron-hole pairs, leading to the enhancement of hydrogen production, the diminishment of pollutants in water under visible light irradiation, and antimicrobial activity against multidrug-resistant pathogens.