Basic and acidic electrolyte mediums impact on MnO₂-Mn₂O₃/Poly-2-methylaniline hexagonal nanocomposite pseudo-supercapacitor

Abstract

Abstract A highly efficient MnO 2 -Mn 2 O 3 /Poly-2-methylaniline (MnO 2 -Mn 2 O 3 /P2MA) hexagonal nanocomposite is synthesized using a one-pot technique involving oxidation polymerization. The hexagonal morphology and crystalline nature of this nanocomposite, as evidenced by the XRD pattern, affirm its exceptional characteristics. The electrical properties are assessed through charge/discharge behavior and cyclic voltammetry curves, elucidating the storage capabilities of this pseudo supercapacitor using different electrolytes NaOH and HCl. The fabricated supercapacitor exhibits impressive efficiency values of 22 F g −1 in a basic medium and a notably higher 72 F g −1 in an acidic medium at a current density of 0.2 A/g. Similarly, the power density values are calculated at 480 and 478 W.kg −1 for the basic and acidic electrolyte, correspondingly. In the basic medium, the series resistance (R S ) and charge transfer resistance (R CT ) are 5.2 and 0.7 Ω, respectively. In the acidic medium, these values are notably lower, with R S at 2.82 Ω and R CT at 0.2 Ω. Remarkably, even after 500 cycles, the supercapacitor stability remains high at 95% in both media, underscoring the enduring stability attributed to the oxides and polymer materials within the supercapacitor. The combination of cost-effectiveness, ease of fabrication, and potential for mass production positions this supercapacitor as a promising candidate for industrial applications of polymer-based supercapacitors.