A comparative study of sequentially layer-deposited and co-deposited Co-Mn oxides as potential redox capacitors

作者：Gobal Fereydoon; Jafarzadeh Sanaz^*

来源：Journal of Solid State Electrochemistry, 2012, 16(4): 1561-1569.

DOI：10.1007/s10008-011-1561-y

• Co-Mn oxides
• Layered oxides
• Potentiostatic deposition
• Specific capacitance
• Supercapacitor

Layers of cobalt and manganese oxides were co-deposited or deposited on top of each other or next to each other by potentiostatic method onto stainless steel substrate. Deposition potentials of 1 and -1 V for the anodic and cathodic depositions were employed. Specific capacitance values in the range of 38.5-78 F g(-1) were found with cobalt oxide on top of manganese oxide having the lowest and manganese oxide on top of cobalt oxide having the highest capacitances. The usefulness of the electrodes was characterized by cyclic voltammetry, charge-discharge cycling, and electrochemical impedance spectroscopy in 2 M NaOH electrolyte for redox supercapacitor applications. The latter presented the best charge/discharge behavior with no voltage drop due to lower ohmic resistance in prepared substrate; although the steadiest current observed in the course of voltammetry was due to the former. The evaluated double layer and specific capacitances for co-deposited sample according to the impedance studies were 1.75 and 47.5 F g(-1), respectively, being in good agreement with voltammetric measurements.

• 出版日期2012-4