Study Of Porous Active Carbon Materials For Super-Capacitors

Super-capacitor is regarded as a new kind of energy sources because of their excellent properties such as high power density, fasting charge and recharge and long usage life. The properties of super-capacitor made from carbon material depend on the active carbon structure parameters such as specific surface area, surface functional groups and the pore dimension and its distribution. Because all these parameters base on the process which active carbon was made, it is important to research and develop new ways to prepare active carbon and control the pore structures for super-capacitor application.With FeCl₃ as catalyst, raw carbon (LAC) was successfully modified by CO₂ used as activation agents. The adsorption performance of activated carbon (AC) was characterized by ethanol, methylene blue and VB₁₃; the surface morph was observed through SEM; the pore structure of AC was measured by N₂ at 77K. The pore distribution was characterized by DFT and the BET specific surface area of AC was calculated. The content of surface functional groups was measured by alkali titration, and the electro-chemical performance of active carbon was studied, such as the cyclic voltammetry, the cyclic life and the AC impedance analysis; the influences of the electrical conductors on the electro-chemical performance was also investigated.The experiment results show that the active carbon has the best properties when the pressure is 20Kpa ,active temperature is 900℃, the active time is 2.5h and the rate of Fe to carbon is 0.04. The adsorption content of the alcohol, methylene blue and the VB₁₂ are 2828mg/g, 441mg/g and 181mg/g respectively. The BET specific surface area and the total cubage increase twice. The BJH specific surface is about 3 times that of the...