High-Conductivity and High-Capacitance Electrospun Fibers for Supercapacitor Applications

Electrospinning is a simple method for producing nanoscale or microscale fibers from a wide variety of materials. Intrinsically conductive polymers (ICPs), such as polyaniline (PANI), show higher conductivities with the use of secondary dopants like m-cresol. However, due to the low volatility of most secondary dopants, it has not been possible to electrospin secondary doped ICP fibers. In this work, the concept of secondary doping has been applied for the first time to electrospun fibers. Using a novel design for rotating drum electrospinning, fibers were efficiently and reliably produced from a mixture of low- and high-volatility solvents. The conductivity of electrospun PANI-poly(ethylene oxide) (PEO) fibers prepared was 1.73 S/cm, two orders of magnitude higher than the average value reported in the literature. These conductive fibers were tested as electrodes for supercapacitors and were shown to have a specific capacitance as high as 3121 F/g at 0.1 A/g, the highest value reported, thus far, for PANI-PEO electrospun fibers.