Carbon Nanotube Based Electrochemical Supercapacitor Electrodes.

摘要

A specific capacitance of about 300 F/g was achieved by KOH activated PAN/CNT films as compared to less than 120 F/g achieved for CO2 activated samples. The PAN/CNT (80/20) film impregnated with 6M KOH and activated at 800 deg C resulted in maximum specific capacitance. Samples activated at all process conditions resulted in narrow pore size distribution of 1-5 nm. The specific capacitance measured from this study correlated to micropore surface areas. The energy density increased from approximately 2 Wh/Kg in 6M KOH to approximately 22 Wh/kg in BMIMBF4/AC by increasing the operating voltage from 0.8 V to 3.0 V respectively. The energy density (approximatley 22Wh/kg) achieved from this study is in the range obtained for batteries. Capacitance of KOH activated PAN/CNT (80/20) films even after 10,000 charge/discharge cycles, was substantially higher than that for the KOH activated buckypapers. Electrospun PAN, PAN/SAN, and PAN/SAN/CNT fiber mats as well as bulk composite films were also stabilized, carbonized, and processed into electrochemical capacitor electrodes. Results of these studies are also reported.