OCM and Impedance Analysis of Polypyrrole
Abstract
Quartz crystal microbalance studies have been used to identify anion insertion or cation insertion in polypyrrole films. In the conditions where only a single species is inserted, impedance measurements have been used to characterized the processes of charge injection and diffusion in the films. Impedance behavior of electroactive polymer films display three distinct regions, characterized by different relaxation times. At high frequencies, the simultaneous injection of holes (during oxidation of the polymer) and counterion movement (to maintain charge neutrality) is the rate controlling process. At intermediate frequencies, diffusion of holes and ions in the film is rate limiting. At the lowest frequencies, the finite thickness of the film causes the impedance to become purely capacitive (redox capacity region). Keywords: Polymer, Impedance polypyrrole, Insertion electrode.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1990
- Accession Number
- ADA229185
Entities
People
- Heai-ku Park
- Mary M. Lien
- W. H. Smyrl
Organizations
- University of Minnesota