Synergistic Effect of PVA/PVP/CuO Polymer Nanocomposites: Flexible Solid-State Asymmetric Supercapacitors

The electrochemical capacitors that use polymer nanocomposite electrode are the most efficient electrical energy storage devices due to their superior power density, quick charge/discharge, long cycle life and high degree of safety. The electrochemical performance of transitional metal oxide-based polymer nanocomposites electrode has been synthesized by solution casting method. The prepared polymer nanocomposites (PNCs) physical and electrochemical properties such as structural, morphology, cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS) were investigated. Subsequently, the solid-state asymmetric supercapacitor was assembled with (PVP/PVA/CuO X wt.%)//activated carbon in 6 M KOH electrolyte. Benefiting from the efficient pseudocapacitive properties of the flexible polymer nanocomposite positive electrode and activated carbon as a negative electrode. The PVP/PVA/5 wt.% CuO polymer nanocomposite electrode demonstrates a superior specific capacitance of 7.90 F g-1 at a current density of 2 A/g. The device has examined to life time application for cycling retention study and charge/discharge stability for 5 wt.% of PNCs electrode exhibited 88% capacity retention after 5000 GCD cycles at current density of 5 A g-1. The assembled flexible solid-state asymmetric supercapacitor exhibits a high energy density of 6.34 Wh kg–1 and power density of 566.06 W kg–1. These electrochemical results showed that the polymer nanocomposite exposed the strong synergistic effect between CuO nanoparticles and PVP/PVA blend polymer matrix and being facilitated by fast charge transfer, charge transfer resistance and the improved capacitance performances. Moreover, the fabricated asymmetric supercapacitors (ASCs) device also shows an excellent stability of electrochemical performance and hence finds a promising candidate for energy storage in supercapacitor as a flexible power source for wearable and portable electronics.