Electrochemical and scanning transmission X-ray microscopy studies of MnO2 and Mn3O4 for supercapacitor cathodes: Influence of fabrication method and electrochemical activation on charge storage

This investigation is motivated by increasing interest in Mn3O4 as a promising alternative to MnO2 for supercapacitors with high active mass and the need for better understanding of charging and electrode activation mechanisms. High energy ball milling (HEBM) of chemically precipitated MnO2 and Mn3O4 in the presence of quercetin resulted in significant capacitance increase. The use of Mn2+ salts for Mn3O4 synthesis facilitated the application …