MILD SOLUTION ROUTE TO MIXED-PHASE MnO2 WITH ENHANCED ELECTROCHEMICAL CAPACITANCE

Mild chemical bath route at 60-80 degrees C led to the redox reaction between MnSO4 and KMnO4 to form MnO2. The as-synthesized MnO2 was a mixture of both alpha- and delta-phases, which has enhanced electrochemical capacitance performances. Pure alpha-, delta-and gamma-MnO2 were also chemically prepared in the current solution system. The electrochemical performances of the as-prepared MnO2 samples were evaluated as an electrode for supercapacitor by recording cyclic voltammograms and galvanostatic charge-discharge curves. The crystallographic structure of MnO2 was found to be determined by the chemical bath reaction temperature and time. In the current work, we purposefully designed the optimum reaction parameters to synthesize high performance mixed-phase MnO2 through mild chemical bath route, ultimately for enhancing the capacitance of powder-based electrodes.