Effect of Na and Mn substitution in perovskite type LaFeO3 for storage device applications

The feasibility of perovskite-type La0.8Na0.2Fe0.8Mn0.2O3 for structural, electrical, and electrochemical property for high rate capability in supercapacitor has been explored at room temperature. Nanocrystalline La0.8Na0.2Fe0.8Mn0.2O3 was prepared via a modified Pechini route. Structural and surface morphology was done by X-ray diffraction and field emission scanning electron microscopy, respectively. Optical band gap was evaluated to be similar to 1.59 eV. The bulk conductivity of the electrode under study was found to be similar to 4.54 x 10(-7)S cm(-1). Specific surface area was found to be similar to 8.16 m(2) g(-1). The electrode property has been studied via cyclic voltammetry, electrochemical impedance spectroscopy (EIS), and charge-discharge analysis. The presence of a redox peak in cyclic voltammetry reveals typical pseudocapacitor behavior and recorded in the potential window -0.35 to 1 V. Faradic charge transfer resistance (R-ct) was found to be similar to 53.85 Omega (R-s = 2.03 Omega) from EIS, and the charge-discharge characteristic for a hundred cycles shows an initial capacity fading up to 25 cycles, beyond which it becomes stable at similar to 6.2 Fg(-1).