Effect of doping level and morphology on the transport properties of poly(4,4 '-dipentoxy-2,2 '-bithiophene)

The transport properties of the title conducting polymer (polyET2), synthes ized using two different supporting electrolytes, have been studied over a wide range of electrochemical doping levels. The Hall mobility of the mater ial is found to be sensitive to both the carrier concentration and the mole cular order, decreasing as a function of the free carrier concentration, an d becoming greater with increasing molecular order. The mobilities achieved with this method are the highest so far known for this kind of material. A conduction model based on overlapping cation states is proposed.