| dc.description.abstract |
In the present study, the activated carbon obtained from China Carbon Steel Company was used as the electrode for the super capacitor. The different heat treatment temperature, atmosphere, and the particle size of activated carbon were controlled and their effects were studied comprehensively to understand the electrochemical behavior of super capacitor. 1M TEABF4 (Tetraethylammonium Tetrafluoroborate)/PC (Propylene) was used as an electrolyte. The effects of different heat treatment temperatures (450, 600, 750, 850 and 950 °C) on the capacitors were investigated. This study shows that with increasing the heat treatment temperature, the oxygen content on the surface of activated carbon and the specific surface area reduced leading to decrease in the capacitance at low-current density. However, the decrease in the content of the oxygen-containing functional groups can improve the durability of the capacitor (cycle stability, high-rate performance, leakage current characteristics, etc.). On the basis of the above experimental results, the effects of heat treatment on the capacitors were investigated under different atmospheres at 750°C. Also, we doped Nitrogen in the activated carbon by using different heat treatment atmosphere (Melamine, NO, and NH3) to improve the performance of the capacitors.
Further, the activated carbon with different particle size distribution was heat treated at 750 °C in the nitrogen atmosphere. The effect of particle size on the properties of super capacitor was investigated. It is found that the smaller the particle size, the more the amount of oxygen functional groups is contained on the surface of the carbonaceous material and as result of which affects the electrochemical properties of the capacitor (cycle stability, high-speed stability, leakage current characteristics, etc.). | en_US |