Capacitive Behavior and Charge Storage Mechanism of Manganese Dioxide in Aqueous Solution Containing Bivalent Cations

Manganese dioxide shows an ideal capacitive behavior in the aqueous solution containing bivalent cations . A specific capacitance value as high as in electrolyte was measured at a sweep rate of . A cycle life test was also performed and no capacity loss of electrode was found after , which indicates the electrode possesses a good cycling property in the aqueous electrolyte containing bivalent cations . X-ray photoelectron spectroscopy data reveal that the ions in the electrolyte are involved in the charge storage process of manganese dioxide in an aqueous system and correspondingly a part of ions will become to ion to balance the charge.