The Capacitive Behaviors of Manganese Dioxide Thin-Film Electrochemical Capacitor Prototypes. (23rd October 2011)

• Record Type: Journal Article
• Authors: Pang Pang, Suh Cem Suh Cem; Wee Wee, Boon Hong Boon Hong; Chin Chin, Suk Fun Suk Fun
• Other Names: Ozoemena Ozoemena Kenneth I. Kenneth I. Academic Editor.
• Is Part Of: International journal of electrochemistry. Volume 2011(2011)
• Publication Date: 2011-10-23
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; 660.297
• DOI: 10.4061/2011/397685
• Languages: English
• ISSNs: 2090-3529

Abstract

Abstract : We have documented the fabrication of manganese dioxide (MnO2 ) thin-film electrochemical capacitor (EC) prototypes with dual-planar electrode configuration. These EC prototypes exhibited good capacitive behaviors in mild Na2 SO4 aqueous electrolyte. Enhanced capacitive behaviors of EC prototypes were observed upon prolonged voltammetric cycling which could be associated with microstructural transformation of MnO2 thin-film electrodes from densely packed plate-like to irregular petal-like surface morphology. Effects of voltammetric scan rates, prolonged voltammetric cycling, electrolyte composition, and electrolyte concentration on the surface morphology of MnO2 thin-film electrodes, and associated capacitive behaviors of MnO2 thin-film EC prototypes were investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge/discharge (GCD) techniques. Results of both CV and EIS indicated that thin-film MnO2 EC prototypes exhibited the highest specific capacitance of 327 F/g in 0.2 M Na2 SO4 aqueous electrolyte. Being environmentally benign and cheap, MnO2 thin-film electrochemical capacitors have high potential utility as pulsed power sources, as well as load-leveling functions in various consumer electronic devices.