Abstract:
Conjugated polymers are promising materials for the use as soft actuators or as electrodes in
batteries and the actuation mechanism of such polymers highly depends on the diffusion of
counter ions into these polymers during the redox process. Among several conjugated polymers,
polypyrrole doped with large immobile dodecylbenzene sulfonate anions (PPy/DBS) operating
in aqueous electrolytes has been identified as one of the successful systems suitable for the use
as artificial muscles. The insertion and expulsion of counter ions into PPy/DBS films when
operating in aqueous electrolytes determines the speed of response of such films and is
quantitatively measured by the parameter, the effective diffusion coefficient. The objective of the
present work is to determine the effective diffusion coefficients for PPy/DBS films prepared by
different preparation processes in order to compare the yield values. For this PPy/DBS films
were electroplolymerized on Pt wire under galvanostatic mode and electrochemically cycled in
0.1M LiCl aqueous electrolytes. The effective diffusion coefficient for 10 𝜇𝑚 PPy/DBS films
prepared as a single layer was found to be 3.315×10−12𝑀2S-1. Whereas it was
9.9433×10−12 𝑀2 S-1 when the same thickness film was prepared as 2 𝜇𝑚 layer by layer rather
than single layer. This finding indicates that the speed of response PPy/DBS films improves
considerably when it is prepared as layer by layer
