Journal of Polymer Science Part B: Polymer Physics, Vol.37, No.20, 2845-2850, 1999
Conduction behavior of doped polyaniline films at high current density regime
The conduction behavior at high current density at room temperature and above of polyaniline (PANI) films doped with HCl and camphor sulfonic acid (HCSA), respectively, is reported. It is found that the current density deviates strongly from the linear relation with the electric field in high current density region, and a saturation of the current density is observed. The maximum current density J(m) seems to be proportional to the conductivity of the sample and hence, for PANI doped with HCl, J(m) is about 200 A/cm(2) whereas for HCSA doped samples, J(m) can reach more than 1,200 A/cm(2). The saturation of current density is interpreted as being caused by space charge accumulation at the insulating barrier regions and a dedoping effect in the conduction domains due to the detraping of the ions under high fields.