Show simple item record

dc.contributor.author
Aeppli, Meret
dc.contributor.author
Voegelin, Andreas
dc.contributor.author
Gorski, Christopher A.
dc.contributor.author
Hofstetter, Thomas B.
dc.contributor.author
Sander, Michael
dc.date.accessioned
2022-08-02T07:35:21Z
dc.date.available
2018-01-28T11:34:37Z
dc.date.available
2018-02-16T15:38:04Z
dc.date.available
2022-08-02T07:35:21Z
dc.date.issued
2018-01-16
dc.identifier.issn
0013-936X
dc.identifier.issn
1520-5851
dc.identifier.other
10.1021/acs.est.7b04411
en_US
dc.identifier.uri
http://hdl.handle.net/20.500.11850/235669
dc.identifier.doi
10.3929/ethz-b-000235669
dc.description.abstract
Iron (oxyhydr-)oxide reduction has been extensively studied because of its importance in pollutant redox dynamics and biogeochemical processes. Yet, experimental studies linking oxide reduction kinetics to thermodynamics remain scarce. Here, we used mediated electrochemical reduction (MER) to directly quantify the extents and rates of ferrihydrite, goethite, and hematite reduction over a range of negative reaction free energies, ΔrG, that were obtained by systematically varying pH (5.0 to 8.0), applied reduction potentials (−0.53 to −0.17 V vs SHE), and Fe2+ concentrations (up to 40 μM). Ferrihydrite reduction was complete and fast at all tested ΔrG values, consistent with its comparatively low thermodynamic stability. Reduction of the thermodynamically more stable goethite and hematite changed from complete and fast to incomplete and slow as ΔrG values became less negative. Reductions at intermediate ΔrG values showed negative linear correlations between the natural logarithm of the reduction rate constants and ΔrG. These correlations imply that thermodynamics controlled goethite and hematite reduction rates. Beyond allowing to study iron oxide reduction under defined thermodynamic conditions, MER can also be used to capture changes in iron oxide reducibility during phase transformations, as shown for Fe2+-facilitated transformation of ferrihydrite to goethite.
en_US
dc.format
application/pdf
en_US
dc.language.iso
en
en_US
dc.publisher
American Chemical Society
en_US
dc.rights.uri
http://rightsstatements.org/page/InC-NC/1.0/
dc.title
Mediated Electrochemical Reduction of Iron (Oxyhydr-)Oxides under Defined Thermodynamic Boundary Conditions
en_US
dc.type
Journal Article
dc.rights.license
In Copyright - Non-Commercial Use Permitted
dc.date.published
2017-12-04
ethz.journal.title
Environmental Science & Technology
ethz.journal.volume
52
en_US
ethz.journal.issue
2
en_US
ethz.journal.abbreviated
Environ. Sci. Technol.
ethz.pages.start
560
en_US
ethz.pages.end
570
en_US
ethz.version.deposit
publishedVersion
en_US
ethz.identifier.wos
ethz.identifier.scopus
ethz.publication.place
Washington, DC
en_US
ethz.publication.status
published
en_US
ethz.leitzahl
ETH Zürich::00002 - ETH Zürich::00012 - Lehre und Forschung::00007 - Departemente::02350 - Dep. Umweltsystemwissenschaften / Dep. of Environmental Systems Science::02721 - Inst. f. Biogeochemie u. Schadstoffdyn. / Inst. Biogeochem. and Pollutant Dynamics::03850 - McNeill, Kristopher / McNeill, Kristopher
en_US
ethz.leitzahl.certified
ETH Zürich::00002 - ETH Zürich::00012 - Lehre und Forschung::00007 - Departemente::02350 - Dep. Umweltsystemwissenschaften / Dep. of Environmental Systems Science::02721 - Inst. f. Biogeochemie u. Schadstoffdyn. / Inst. Biogeochem. and Pollutant Dynamics::03850 - McNeill, Kristopher / McNeill, Kristopher
en_US
ethz.date.deposited
2018-01-28T11:34:37Z
ethz.source
FORM
ethz.eth
yes
en_US
ethz.availability
Open access
en_US
ethz.rosetta.installDate
2018-02-16T15:38:06Z
ethz.rosetta.lastUpdated
2022-03-28T19:12:20Z
ethz.rosetta.exportRequired
true
ethz.rosetta.versionExported
true
ethz.COinS
ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.atitle=Mediated%20Electrochemical%20Reduction%20of%20Iron%20(Oxyhydr-)Oxides%20under%20Defined%20Thermodynamic%20Boundary%20Conditions&rft.jtitle=Environmental%20Science%20&%20Technology&rft.date=2018-01-16&rft.volume=52&rft.issue=2&rft.spage=560&rft.epage=570&rft.issn=0013-936X&1520-5851&rft.au=Aeppli,%20Meret&Voegelin,%20Andreas&Gorski,%20Christopher%20A.&Hofstetter,%20Thomas%20B.&Sander,%20Michael&rft.genre=article&rft_id=info:doi/10.1021/acs.est.7b04411&
 Search print copy at ETH Library

Files in this item

Thumbnail

Publication type

Show simple item record