Study of double perovskite La2B(II)MnO6 (B: Ni, Co, Cu) as electrode materials for energy storage

In this paper, the study of the potential capacity of energy storage in supercapacitors containing oxide La2B(II)MnO6 (with B = Cu, Co, Ni) as the electrode material is presented. The mixed oxides are prepared by route of citrate precursors, starting from the nitrates of the corresponding metallic cations. The samples were calcined at 800 degrees C. The material was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The electrochemical characterization was performed through cyclic voltammetry (CV), galvanostatic charge/discharge measurements (GCD) and electrochemical impedance spectroscopy (EIS) in a three-electrode cell at room temperature, using a platinum electrode and a hydrogen electrode as counter and reference electrodes, respectively. The working electrode was prepared by a dispersion of the nanocomposite and carbon black in an isopropanol solution added on glassy carbon and covered by a Nafion (R) thin film. Runs were carried out in 0.05--0.95-V range in 0.5 M KOH solution. The cyclic voltamperograms were obtained at varying the scan rates from 10 to 100 mV s(-1). The galvanostatic charge/discharge curves were realize at current density values in the 0.625-31.25 A g(-1) range. The higher capacitance values were obtained for La2CuMnO6. Thus, a specific capacitance of 781.25 F g(-1)at a current density of 3.12 A g(-1), and a power and an energy specific of 72.6 kW kg(-1) and 113.4 Wh kg(-1), were obtained.