Effect of HTAC on preparation of supercapacitors based on nanocomposites of MnO2 : HTAC by direct electrodeposition

An cationic surfactant of Hexadecyl Trimethyl Ammonium Chloride (HTAC) are used to modify morphology of MnO₂ by direct electrodeposition. The deposited nanocomposites of MnO₂ : 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 MnO₂ : HTAC at surfactant concentration below 50 mM is larger than pristine MnO₂ by BET analysis, which results in that the specific capacitance of nanocomposites of MnO₂ : HTAC is larger than pristine MnO₂. The MnO₂ : HTAC nanocomposites show better cycles performance of charge/discharge than pristine MnO₂, because the alkyl chains of cationic surfactants on surface can delay the dissolving of MnO₂ materials in electrolytic solution during cycles. By use of HTAC surfactant, both of the specific capacitance and stability for charge/discharge circles of MnO₂ electrode materials are highly improved.