uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
The initial stages of atmospheric corrosion of iron in a saline environment studied with time-resolved in situ x-ray transmission microscopy
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
Royal Institute of Technology. (Surface and Corrosion Science)
Royal Institute of Technology. (Surface and Corrosion Science)
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and condensed matter physics.
Show others and affiliations
2010 (English)In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 157, no 3, C110-C115 p.Article in journal (Refereed) Published
Abstract [en]

We have investigated atmospheric corrosion of a 50 nm layer of iron covered with a thin layer of NaCl by in situ X-ray transmission spectromicroscopy. We find that upon its deliquescence, a small part of the NaCl layer is rapidly transformed into a sodium oxide (NaOH) species. A large part of the sodium and chlorine ions forms a concentrated solution on the iron surface and becomes segregated, whereby the sodium ions appear stationary and passive during further corrosion progression. In contrast, the chlorine ions appear highly mobile and become concentrated at and travel with the corrosion front, apparently acting as a corrosion catalyst. The corrosion front progression is partly of filiform and partly of radial type. The early iron corrosion products (chloride-containing oxyhydroxides) are short-lived (for some hours) and undergo a transformation as the corrosion front sweeps by from a chlorinated species to a less chlorinated species.

 

 

Place, publisher, year, edition, pages
2010. Vol. 157, no 3, C110-C115 p.
Keyword [en]
catalysts, corrosion, iron, metallic thin films, passivation, segregation, X-ray microscopy
National Category
Physical Sciences
Identifiers
URN: urn:nbn:se:uu:diva-98010DOI: 10.1149/1.3274207ISI: 000274321900044OAI: oai:DiVA.org:uu-98010DiVA: diva2:173165
Available from: 2009-02-06 Created: 2009-02-06 Last updated: 2017-12-14
In thesis
1. In Situ Soft X-ray Spectroscopies Applied to Atmospheric Corrosion And Related Systems
Open this publication in new window or tab >>In Situ Soft X-ray Spectroscopies Applied to Atmospheric Corrosion And Related Systems
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis concerns the application of various soft x-ray spectroscopic methods (soft x-ray absorption, SXA, and emission, SXE) to complex, non-vacuum compatible systems, including liquids and multi-phase systems.

The design, construction, and application of new instrumentation for in situ spectroscopy is described in detail. This includes sample holders using thin soft x-ray transparent membranes to enable measurements on systems completely isolated from vacuum, enabling flow of e.g. liquid or gas. In particular, a versatile setup for time resolved in situ chemical contrast x-ray transmission microscopy (CCXTM) was constructed and implemented. These instruments are expected to be applicable to a wide range of situations, for example in situ studies of chemical reactions, or biological specimen.

The main project concerns atmospheric corrosion of iron in a saline environment, a process that requires the simultaneous presence of the solid (iron, NaCl), liquid (water) and gaseous (air) phases. It is also a highly inhomogeneous process, where lateral and time resolution is important. Using the CCXTM instrumentation, we were able to follow the distribution of all present elements over the sample with time resolution of a few minutes, and also to extract significant chemical information from the absorption edges. We observed e.g. the initial formation of corrosion products and transport of chlorine.

Results from SXE measurements on water molecules in micelle structures are presented. A comparison with calculations reveal influence from the counter-ions, but also some spectral changes that may be attributed to water confinement.

Also presented are angle dependent soft x-ray emission of liquid water, measuring scattered x-rays from different directions respect to the incident x-ray polarization. Existing preliminary theoretical expectations for the polarization dependence are contradictory. Our experiments show that a small angular anisotropy seems to be retained from the free molecule case.

Place, publisher, year, edition, pages
Uppsala: Universitetsbiblioteket, 2009. ix, 85 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 595
National Category
Physical Sciences
Identifiers
urn:nbn:se:uu:diva-9540 (URN)978-91-554-7397-6 (ISBN)
Public defence
2009-02-27, Häggsalen, Ångström Laboratory, Lägerhyddsvägen 1, Polacksbacken, Uppsala, 13:15 (English)
Opponent
Supervisors
Available from: 2009-02-06 Created: 2009-02-06 Last updated: 2010-05-05Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text
By organisation
Molecular and condensed matter physics
In the same journal
Journal of the Electrochemical Society
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 738 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf