Unraveling the electrochemical properties and charge storage mechanisms of lactobacillus-mediated synthesized RGO-titanium silver nanocomposite as a promising binder-free electrode for asymmetric supercapacitor device

A sustainable and scalable technique was developed to synthesize RGO-TiAg nanocomposites at room temperature, utilizing Lactobacillus sp. as an environmentally friendly reducing and stabilizing agent. This approach offers a cost-effective solution for large-scale production. The unique properties of Lactobacillus sp. allow for the reduction of metal ions while inhibiting agglomeration and preserving the stability of the resulting nanocomposites. The addition of reduced graphene oxide (RGO) sheets to the TiAg-based electrode increases its specific surface area, thereby enhancing the electrode's charge-storage capacity by promoting the formation of conductive networks. Furthermore, the hydrophilic oxygen groups of chemically reduced graphene oxide in the RGO-TiAg nanocomposites facilitate the electrolyte's access to the electrode's pores. Electrochemical analysis revealed that the RGO-TiAg NCs demonstrated the highest specific capacitances of 816.92 F/g at 1.5 A/g. An asymmetric supercapacitor device was fabricated by utilizing a composite electrode composed of RGO-TiAg NCs and activated carbon (AC). Polyvinyl alcohol-Na2SO4 (PVA-Na2SO4) was employed as the electrolyte and electrode separator. The RGO-TiAg NCs//ACarbon assisted ASC supercapacitor device demonstrated a specific capacitance of 256 F/g at 4 A/g, along with tremendous energy and power densities of 53.33 Wh kg 1 and 2 kW kg 1, respectively, at the same current density. The device exhibited a high-power density of 6 kW kg 1 and an energy density of 25 Wh kg 1, with a capacitance retention of 82% even at an ultrahigh current density of 12 A/ g, after 10,000 cycles. Additionally, this work illustrates an effective method for synthesizing nanocomposites that may be used for developing prospective, high-performance supercapacitors for energy storage.