The development of polyaniline–manganese(IV) oxide doped with methane sulfonic acid (MSA) is meritorious as the supercapacitor electrode for its energy storage behavior. In this work, PANI–MnO 2 (PM) nanocomposites were synthesized by facile in situ single‐step oxidative polymerization method with different weight compositions, keeping constant weight of PANI and varying the weight of MnO 2 . The structural, morphological, and surface phenomena of PM nanocomposite were characterized by powder X‐ray diffraction (XRD), Fourier‐transform infrared (FT‐IR) spectroscopy, Raman spectroscopy, Brunauer–Emmett–Teller (BET) isotherm, field emission scanning electron microscopy (FE‐SEM), and X‐ray photoelectron spectroscopy (XPS). The electrochemical performances were investigated in a two‐electrode configuration using 1 M H 2 SO 4 as electrolyte by cyclic voltammetry (CV), galvanostatic charging/discharging (GCD), and electrochemical impedance spectroscopy (EIS). The PM36 nanocomposite with a weight composition of PANI 63.63% and MnO 2 36.36% exhibited superior electrochemical characteristics with a specific capacity ( Q ) of 43.3 C g −1 with a specific energy ( E ) of 7.21 W h kg −1 and a specific power ( P ) of 150 W kg −1 at 0.25 A g −1 . The fabricated supercapacitor has 86.5% capacitive retention at the end of 13 500 cycles at 0.4 V s −1 proving its suitability for sustainable and durable energy storage applications.
Babu et al. (Fri,) studied this question.