Direct in situ conductance evidence for non-faradaic electrical processes in poly(3-methylthiophene)

Registration of the conductance after the end of the electrochemical polyme risation of 3-methylthiophene (PMT) indicated a large conductance increase at open circuit. Further in situ conductance measurements with the polymeri c film in Bu4NPF6/acetonitrile base solution provided direct evidence for t hat - after the oxidation of the film - the firial achievement, the accompl ishment of the state of high conduction is not necessarily coupled with cur rent flow any more. The non-faradaic step which may explain this observatio n is described as a chemical reorganisation within the film, which involves the transformation of solvated polymer segments to a more conjugated, non- solvated form. (C) 2000 Elsevier Science Ltd. All rights reserved.