Electrochemical performance of potentio-dynamically deposited Co3O4 electrodes: influence of annealing temperature

Co₃O₄ thin films were deposited potentiodynamically on to the stainless steel substrate. Prepared samples were annealed within the temperature range 473 K to 873 K by the interval of 100 K. XRD study reveals cubic crystal structure of Co₃O₄. FE-SEM showed compact agglomerated granular type morphology. Electrochemical characterization of electrodes showed pseudo capacitive behavior. Maximum value of specific capacitance (441.17 F/g) was achieved at the scan rate 2 mV/s in 1 M KOH with 87.88% stability. Charge–discharge curves showed nonlinear behavior and used to calculate the specific energy, specific power and columbic efficiency which were 20.98 W/kg, 15.96 kW/kg and 86.63% respectively. EIS of complex impedance spectra showed internal resistance ~0.9435 Ω.