In situ conductivity measurements of polythiophene partially containing 3,4-ethylenedioxythiophene and 3-hexylthiophene

Optical and electrochemical properties of a novel polythiophene partially containing 3,4-ethylenedioxythiophene (EDOT), poly(3,3″″-dihexyl-3′,4′,3‴,4‴-diethylenedioxy-2,2′:5′,2″:5″,2‴:5‴,2″″-quinquethiophene), in a neutral state, which was synthesized by polycondensation using direct C-H coupling reaction, were firstly investigated. In situ electrical conductivity of the doped polymer film was measured simultaneously with doping levels at different potentials to yield charge carrier mobilities as a function of doping level of the polymer. The highest conductivity was found to be around 10 1 S cm −1 , which is almost one-order higher than that of an EDOT-containing polythiophene obtained by electrolytic polymerization, poly(3″,4″-ethylenedioxy-2,2′:5′,2″-terthiophene).