Supercapacitor performances of activated carbon fiber webs prepared by electrospinning of PMDA-ODA poly(amic acid) solutions

The poly(amic acid) (PAA) solution was successfully electrospun at voltages between 13 and 15 kV, forming yellow webs of fibers with diameters of 2-3 mum. The PAA web was then imidized with yield of about 81%. The imidized webs were carbonized in the temperature range from 700 to 1000degreesC under a nitrogen atmosphere with yields greater than or equal to 53%. The flexible carbonized fiber web with the amorphous structure and the relatively high electrical conductivity of 2.5 S/cm at 1000 degreesC appears to be a good candidate material for the electrode of electrical double layer capacitors (EDLCs). The carbonized webs were activated under steam in the temperature range of 650-850 degreesC resulting surface specific surface area of 940-2100 m(2)/g. The activated carbonized webs were tested electrochemically for the performances as electrodes of EDLC in 30 wt.% KOH aqueous solution. The specific capacitance was 175 F/g even at a high current density of 1000 mA/g. (C) 2004 Elsevier Ltd. All rights reserved.