The electronic transport mechanism for ion implanted and chemically doped polyanilinefilms was investigated through temperature dependent dc conductivity measurements over thetemperature range 1.8 – 300K. Chemically synthesized emeraldine base polyaniline free-standingfilms (∼40 µm thick) were irradiated by Ar ions at an energy of 90 keV and doses ranging from 1 ×1014 to 3 × 1017 cm-2 to an estimated thickness of 100 nm. Chemical modification of Polyanilinefilms consisted of doping with 1.0 M H2SO4.
Ion implantation and chemical doping were found to considerably increase the roomtemperature dc conductivity of polyaniline films reaching values up to 800 S cm-1and 8 S cm-1, respectively. Both ion irradiated and chemically doped polyaniline films exhibit p-type conduction.An increase in the irradiation dose increases the stability of the conducting layer compared tochemical doping. In both cases the samples are on the insulator side of the metal-insulatortransition, where cr(T) exhibits a common temperature dependent characteristic of the variablerange hopping (VRH) transport mechanism:σ(T) = σ (0) exp[ - (To / T)m ] (1)where m = 0.5 and To = 103 to 104K. The influence of electron-electron Coulomb the low temperature VRH of ion implanted and chemically doped polyanilCinoeu floilmmbs iisn tperreascetniotend