In situ XANES study of galvanostatic reduction of the passive film on iron

Journal Article · Wed Mar 01 04:00:00 EST 1995 · Journal of the Electrochemical Society

DOI:https://doi.org/10.1149/1.2048524· OSTI ID:40305

Davenport, A J; Vitus, C M ^[1]; Bardwell, J A ^[2]

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1. Brookhaven National Lab., Upton, NY (United States). Dept. of Applied Science
2. National Research Council, Ottawa, Ontario (Canada). Inst. for Microstructural Sciences

In situ XANES (X-ray absorption near-edge structure) was used to study galvanostatic reduction of the passive film on iron. In a borate buffer, the film appears to be removed in a layer-by-layer fashion by reductive dissolution during the first potential arrest. A burst of dissolution takes place at the end of the arrest for slow reduction rates. During the course of reduction, the remaining film shows a composition change from ferric oxide toward Fe{sub 3}O{sub 4}. This may indicate that the film has an inner layer of Fe{sub 3}O{sub 4}. Galvanostatic reduction of the passive film grown on iron in 0.1M KOH leads to complete reduction of the passive film to ferrous oxide or hydroxide without any detectable dissolution.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 40305
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 3 Vol. 142; ISSN 0013-4651; ISSN JESOAN
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORATES
IRON
IRON OXIDES
MONITORING
PASSIVATION
POTASSIUM HYDROXIDES
PROTECTIVE COATINGS
REDUCTION
VALENCE