Rheological phase synthesis and electrochemical performance of Co3O4 for supercapacitors

Co3O4 was prepared by rheological phase reaction, and the effect of pyrolyzing temperature on the electrochemical performance of Co3O4 was investigated. XRD shows that higher temperature treatment results in sharper diffraction peaks, indicating an increase of particle size of Co3O4. The result of TEM shows that the particle sizes of Co3O4 are about 200 nm. The optimum pyrolyzing temperature is confirmed to be 600°C, and Co3O4 prepared at this temperature exhibits 390.8 F g−1 of specific capacitance in 6 M KOH electrolyte at the scan rate of 5 mV s−1. Co3O4 prepared at the temperature of 600°C shows an excellent cyclability.