Rutherford Backscattering Studies of Polypyrrole Films: II . Effect of Ionic Size on Mobility
1995; Institute of Physics; Volume: 142; Issue: 2 Linguagem: Inglês
10.1149/1.2044024
ISSN1945-7111
AutoresJesse S. Wainright, Christian A. Zorman,
Tópico(s)Fuel Cells and Related Materials
ResumoIonic diffusion in polypyrrole films has been studied with ex situ Rutherford backscattering spectrometry. Polypyrrole films were deposited from aqueous electrolytes containing one of the following salts: sodium perchlorate, sodium xylene‐sulfonate, or poly(sodium 4‐styrene‐sulfonate). The ionic content of the films was determined as a function of potential (steady‐state results) and as a function of the charge passed during a potentiostatic oxidation or reduction. Results were also obtained for films which were ion exchanged by potential cycling in alkali halide electrolytes. Diffusion coefficients on the order of were obtained for the , Na+, and Cs+ ions. The relative mobilities of the ions are in agreement with their size, assuming the alkali metal cations retain their hydration sheaths within the polymer matrix. Thus perchlorate was found to have the highest diffusion coefficient, while the poly(styrene‐sulfonate) anion was found to be the least mobile.
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