Effect of HTAC on preparation of supercapacitors based on nanocomposites of MnO<inf>2</inf> : HTAC by direct electrodeposition

Abstract

An cationic surfactant of Hexadecyl Trimethyl Ammonium Chloride (HTAC) are used to modify morphology of MnO 2 by direct electrodeposition. The deposited nanocomposites of MnO 2 : HTAC are composed of nanosheets. The manganese dioxide has shown the highest specific capacitance of 350.02 F/g. Specific surface area of the nanocomposites of MnO 2 : HTAC at surfactant concentration below 50 mM is larger than pristine MnO 2 by BET analysis, which results in that the specific capacitance of nanocomposites of MnO 2 : HTAC is larger than pristine MnO 2 . The MnO 2 : HTAC nanocomposites show better cycles performance of charge/discharge than pristine MnO 2 , because the alkyl chains of cationic surfactants on surface can delay the dissolving of MnO 2 materials in electrolytic solution during cycles. By use of HTAC surfactant, both of the specific capacitance and stability for charge/discharge circles of MnO 2 electrode materials are highly improved.