Pulsed electrodeposition of mesoporous cobalt-doped manganese dioxide as supercapacitor electrode material

摘要

Cobalt-doped MnO2, as electrode material for supercapacitor, was synthesized by pulse electrodeposition method. The morphology and structure of the products were characterized by X-ray diffraction (XRD) and field-emission scanning electron microscope (FE-SEM). The results show that the crystal structure of the products is γ-type, and the samples reveals a porous texture composed of manganese oxide nanosheets. Cyclic voltammetry (CV), electrochemical impedance spectrometry (EIS), and galvanostatic charge-discharge tests indicate that doping cobalt has great effect on the electrochemical performance of manganese dioxide material. A specific capacitance of 354 F g~(-1) is obtained when the molar ratio of Mn to Co is 200:10. After 100 charge-discharge cycles in 6 M KOH solution, the specific capacitance stabilized at 333.6 F g~(-1), exhibiting excellent capacitance retention ability.