Mechanism of dc conduction in ferric chloride doped poly(3-methyl thiophene)

Poly(3-methyl thiophene) has been synthesized by chemical oxidation method in an inert atmosphere using ferric chloride as a dopant. The doping level varies from 0.1 to 2.0 M. The dc conductivity has been measured in the temperature range 20–300 K. The observed dc conductivity data has been analyzed in the light of existing theoretical models. Different Mott’s parameters such as characteristic temperature (T₀), density of states at Fermi level [N(E_F)], average hopping energy (W) and the average hopping distance (R) have been evaluated that agree well with the values reported earlier for the other conjugated polymers. A detailed analysis of the mechanism of charge transport in this system has been reported.