Effect of deposition current density on the linear actuation behaviour of PPy(CF3SO3) films

Free-standing films of PPy(CF3SO3) were galvanostatically electropolymerised in propylene carbonate on a stainless steel electrode using different deposition current densities. The actuation performance of these films in an aqueous 1.0 M NaPF6 electrolyte was investigated by in situ measurements of electrochemomechanical deformation (ECMD) during cyclic voltammetry experiments. The extent of linear strain of the films decreased with a higher deposition current density. X-ray photoelectron spectroscopy was used to estimate the amount of 'disordered carbon', carbonyl carbon and the doping level of the films. These values were related to the strain obtained from ECMD measurements. SEM images revealed a denser film morphology for films deposited using a lower current density.