BROAD-BAND DIELECTRIC-SPECTROSCOPY OF CONDUCTING POLYANILINE

Dielectric spectroscopy can be used to probe both the conduction and p olarisation processes of a wide range of materials, The authors focus on the dielectric properties of conducting polymers over the frequency range 1Hz to 20GHz. Initial measurements have been made on polyanilin e samples at room temperature. This particular conducting polymer is o f interest since it is a mixed conductor (i.e. showing both electronic and ionic transport). Analysis-of the frequency dependent complex per mittivity can be used to indicate free charge conduction, charge hoppi ng or ionic diffusion. Temperature dependent measurements are required to determine the type of hopping mechanism where such a process is ob served. Experimental results can be compared to range of theoretical m odels that are available from the literature describing these processe s (Nalwa, 1997; Mott and Davies, 1979; and Sheng 1980).