Synthesis and Electrochemical Analyses of Manganese Oxides for Super-Capacitors.

摘要: δ-Phase and α-phase manganese oxides were prepared using a hydrothermal method their electrochemical properties characterized. The influence of calcination temperature on the was studied. Crystallinities studied by X-ray diffraction, scanning transmission electron microscopy utilized to examine morphologies. Average pore sizes specific surface areas samples analyzed Barret-Joyner-Halenda Brunauer-Emmett-Teller methods, respectively. After in range 300 degrees C 600 C, changes morphology crystallinity observed. flower-like shape as synthesized became nanorod-like δ-phase changed α-phase. These may have been due removal water during calcination. Furthermore, transition stage which two phases coexisted Synthesized mixed with carbon sonification, increase electric conductivity induce synergistic effect between pseudo-capacitor double layer capacitor (EDLC). Specific capacitances rate durability each composite investigated cyclic voltammetry 1 M Na2SO4 electrolyte at different scan rates. MnO2 calcined 400 exhibited highest capacitance, probably its high area more porous structure.