Development of perovskite-FeMnO3/MWCNTs/PANI hybrid as an efficient electrode for supercapattery

Abstract

Manganese-based mixed metal oxides are cost-effective and have a wide voltage range, making them promising for electrochemical energy storage. However, they suffer from poor electrical conductivity, structural instability during cycling, and electrolyte dissolution. Conductive polymers are often added to address these issues to improve conductivity and ion transport. However, these polymers undergo volumetric changes (shrinkage and swelling) during cycling. Incorporating carbon nanotubes (CNTs) enhances structural stability, preventing degradation and preserving electrode integrity. In this study, FeMnO₃ was synthesized via a simple hydrothermal method and combined with multiwalled carbon nanotubes (MWCNTs) and polyaniline (PANI) to form a ternary hybrid composite. The synthesized ternary hybrid was characterized using several techniques, including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) and X-ray photoelectron spectroscopy (XPS). The electrochemical performance of the ternary hybrid as an electrode material for energy storage devices was evaluated using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The results demonstrated that the ternary hybrid achieved a high specific capacity of 1415C/g at a current density of 1 A/g, along with a low charge transfer resistance (R_ct) of 2.96 Ω, and retained 88 % of its initial capacity after 10,000 charge-discharge cycles, indicating excellent durability and performance. Moreover, the ternary hybrid showcases the specific capacity of 109.87C/g at 1 A/g in a two-electrode system with energy density (E_d) and power density (P_d) of 15.11 Wh/kg and 130.05 W/kg, respectively.