Biogenic-ecofriendly synthesized SnO2/CuO/FeO/PVP/RGO nanocomposite for enhancing energy density performance of hybrid supercapacitors

In order to overcome the fluctuation in the output of non-dispatchable renewable energy sources, novel energy storage techniques and systems have become more and more important in recent years. Energy storage devices known as supercapacitors have garnered a lot of interest from the various stakeholders. However, the electrochemical behavior of the electrodes and the techniques employed to create the electrode materials ultimately determine how well a supercapacitor energy storage system works. Researchers have increasingly become interested in sustainable approaches, such green synthesis, for the development of electrode materials. In this work, green synthesis approach was used to prepare the SnO2/CuO (R1), SnO2/CuO/PVP (R2) and SnO2/CuO/FeO/PVP/RGO (R3) nanocomposites for superior electrochemical energy storage features. Among the three electrodes, SnO2/CuO/FeO/PVP/RGO decorated nickel foam electrode achieves the specific capacity of 249C/g which is higher than that of SnO2/CuO and SnO2/CuO/PVP having 210 and 108C/g, respectively, at 0.6 A/g current density in three electrode assembly. Owing to its exceptional electrochemical characteristics, composite SnO2/CuO/FeO/PVP/RGO is utilized as an electrode material for batteries that is paired with negatively featured activated carbon (AC) electrode material to create an asymmetric hybrid supercapacitor. The constructed device displays an excellent energy density of 41.7 Wh/kg and power density of 956 W/kg at 1.2 A/g. It also retains 23.3 Wh/kg at increased current density of 15 A/g. Moreover, the device is highly durable as it retains a capacity retention of 94 % after going through 15,000 cycles. Thus, SnO2/CuO/FeO/PVP/RGO prepared via green synthesis approach increases the electrochemical energy storage performance of hybrid asymmetric supercapacitor device. Consequently, Green synthesis, with its inherent benefits over chemical processes, is anticipated to be a viable technique for fabrication of electrode materials for supercapacitors in view of sustainable energy storage applications in the future.