Fabrication of Carbon\nCloth-Enrobed MnFe<sub>2</sub>O<sub>4</sub>@PPy Nanoparticles for\na Flexible Symmetric Supercapacitor\nDevice

Massive improvements in energy storage devices have prompted\nscientists\nto develop physically and chemically electroactive methods for superior\nsupercapacitor (SC) applications. This study focuses on investigating\nthe synergistic impact of transition metal oxides, PPy, and carbon\nsubstrates on the electrochemical performance of SCs. A facile hydrothermal\napproach is employed to synthesize a MnFe<sub>2</sub>O<sub>4</sub>@PPy nanocomposite on carbon cloth (CC). The CC-enrobed MnFe<sub>2</sub>O<sub>4</sub>@PPy nanocomposite, having a mass loading of\n2.7 mg cm<sup>–2</sup>, demonstrates exceptional electrochemical\nperformance in a three-electrode system using aqueous 1 M H<sub>2</sub>SO<sub>4</sub> electrolytes. The electrode exhibits a remarkable\nspecific capacitance of 1169 F g<sup>–1</sup> at 1 A g<sup>–1</sup> current density, alongside an outstanding capacitance\nretention of 87.6% capacity after 5000 cycles. Furthermore, a flexible\nsymmetric supercapacitor (SSC) is constructed by integrating CC-enrobed\nMnFe<sub>2</sub>O<sub>4</sub>@polypyrrole as both anode and cathode,\nwith a poly(vinyl alcohol) (PVA)–H<sub>2</sub>SO<sub>4</sub> gel electrolyte as the separator. This SSC demonstrates promising\nenergy and power densities of 73.6 Wh kg<sup>–1</sup> and 725.9\nW kg<sup>–1</sup>, respectively, and exhibits a long cycle\nlife with 90.13% capacity retention over 5000 cycles. The CC-enrobed\nMnFe<sub>2</sub>O<sub>4</sub>@PPy nanocomposite electrode shows significant\npotential for storing electrochemical energy.