U139871.pdf (13.8 MB)
Spatial distributions within electroactive films
thesisposted on 2014-12-15, 10:35 authored by Lee. Bailey
The spatial distributions of polymer and solvent within three types of polymer modified electrode have been investigated using the technique of neutron reflectivity. The overall aim of this research is to rationalise electrochemical behaviour of polymer modified electrodes through improved knowledge of in situ electrode structure. This may in future assist the design and fabrication of modified electrodes of desired function.;The permselectivity failure of poly(vinylferrocene) has been investigated, with neutron reflectivity used to quantify mobile species transfer which occurs during redox cycling. Short time scale reflectivity studies have allowed observation of the changes in spatial distributions which occur within such films during oxidation and reduction, and rate limiting species transfers have been proposed.;The reaction of the polymer poly(pentafluorophenyl 3-(pyrrol-1-yl)propanoate) with the nucleophile ferrocene-ethylamine has been followed and in particular the progress of the nucleophile's reaction front through the polymer monitored as a function of time. Definite regional differences in polymer structure were identified, which had an effect on the reaction progress.;Studies on a third system looked at the effect of electrolyte pH on the structure of poly(orthotoluidine) films. At high acid concentration films are observed to swell, with the species responsible dependent on acid concentration. Neutron reflectivity was also used to rationalise combined EQCM/PBD responses obtained during redox cycling of poly(orthotoluidine).
Date of award2000-01-01
Awarding institutionUniversity of Leicester