炭气凝胶的微观结构调控及其电化学性能

Microstructure Regulation and Electrochemical Performance of Carbon Aerogel

采用CO_(2)活化工艺对炭气凝胶(Carbon Aerogel,CA)的微观结构进行调控,研究了CA的比表面积对其电化学性能的影响。结果表明,通过控制CO_(2)的活化温度或时间,CA的比表面积在571~1866m^(2)/g范围内可调,但在活化过程中需要选择适当的活化条件,使CA比表面积增加的同时仍能保持孔结构的稳定性。CA的比表面积越大,比电容越大;比表面积为1866 m^(2)/g、电流密度为0.5 A/g的CA比电容达162.4 F/g。此外,电流密度为1 A/g的CA经1000次充放电循环后,电容保持率仍高于96.2%,具有较高的循环稳定性。

The microstructure of carbon aerogel(CA)was regulated by CO_(2)activation process,and the effect of specific surface area on electrochemical properties was studied.The results showed that CA with a specific surface area ranging from 571 to 1866 m^(2)/g could be achieved by controlling the CO_(2)activation temperature or time.However,it was essential to select appropriate activation conditions so as to maintain the stability of the pore structure while increasing the CA specific surface area.The larger the specific surface area of CA,the larger the specific capacitance.CA with a specific surface area of 1866 m^(2)/g achieved a specific capacitance of 162.4 F/g at 0.5 A/g.In addition,when the current density of CA is 1 A/g,the capacitance retention rate is still higher than 96.2%after 1000 charge and discharge cycles,showing high cycle stability.