Reinterpretation of polypyrrole electrochemistry. Consideration of capacitive currents in redox switching of conducting polymers

Journal Article · Wed Aug 22 04:00:00 EDT 1984 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00329a004· OSTI ID:6461454

Feldberg, S W

A simple analysis of the capacitive currents associated with the electrochemical (cyclic voltammetric) switching of a polypyrrole film between its reduced (insulating) and oxidized (electronically conducting) states offers a reasonably precise description of the form of the voltammogram. The theory demonstrates that a unique value for the faradaic component of the switching current cannot be extracted from the cyclic voltammetric data. Thus the number of electrons per pyrrole, ..gamma.., required for switching cannot be uniquely determined. Reported results of gaseous oxidation of a pyrrole film (by O/sub 2/, FeCl/sub 3/, or I/sub 2/) which produces optical and conductance changes comparable to those observed during electrochemical switching also indicate a comparable degree of oxidation (determined by % weight uptake of the oxidant). Here too, irresolvable faradaic and capacitive electron-transfer components render ..gamma.. indeterminate. The same analysis resolved the seemingly anomalous cyclic voltammetric behavior of polythiophene (another electrochemically switched polymer) and in principle is applicable to any polymer or film which can be electrochemically switched from an insulating to an electronically conducting state. 30 references, 6 figures.

• Research Organization: Brookhaven National Lab., Upton, NY
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6461454
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 106:17; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400* -- Electrochemistry
ACCURACY
AZOLES
CHEMICAL REACTIONS
CHEMISTRY
CHLORIDES
CHLORINE COMPOUNDS
COMPARATIVE EVALUATIONS
ELECTROCHEMISTRY
ELEMENTS
FILMS
HALIDES
HALOGEN COMPOUNDS
HALOGENS
HETEROCYCLIC COMPOUNDS
IODINE
IRON CHLORIDES
IRON COMPOUNDS
MATHEMATICAL MODELS
MATHEMATICS
NONMETALS
NUMERICAL ANALYSIS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC POLYMERS
ORGANIC SULFUR COMPOUNDS
OXYGEN
POLYMERS
PYRROLES
REDOX REACTIONS
TRANSITION ELEMENT COMPOUNDS
VOLTAMETRY