An electrochemical quartz crystal microbalance study on growth of and ion transport in electrochemically polymerized poly(paraphenylene vinylene)

Abstract

The electrochemical quartz crystal microbalance technique has been used to study in situ the mass changes that take place during electrochemical growth and redox cycling of the conducting polymer poly( p-phenylenevinylene) (PPV). The polymer material has been grown onto platinum in dimethylformamide using tetraethylammonium tosylate (TOS) or tetraethylammonium tetrafluoroborate (BF 4) as electrolyte salts. The mass change during polymerization of PPV films under various monomer concentrations was studied and also the effect of water added to the polymerization solution. The results show that the polymerization reaction was enhanced when 1. water was added to the polymerization solution, 2. the concentration of monomer material was increased, and 3. when the polymerization was done in presence of a medium-sized anion. When the PPV films were grown with a medium-sized anion (TOS −), cations were inserted and removed during the redox process in order to compensate for the change in charge of the PPV film. The films prepared in presence of a small anion (BF − 4) showed anion motion during the redox cycling.