Journal article
Connecting observations of hematite (alpha-Fe2O3) growth catalyzed by Fe(II)
Environmental science & technology, Vol.44(1), pp.61-67
01/01/2010
DOI: 10.1021/es901882a
PMID: 20039734
Abstract
Electron exchange between aqueous Fe(II) and structural Fe(III) in iron oxides and oxyhydroxides is important for understanding degradation of environmental pollutants through its apparent constitutive role underlying highly reactive "sorbed Fe(II)" and by catalyzing phase interconversion among these minerals. Although a mechanistic understanding of relationships between interfacial Fe(II)(ads)-Fe(III)(oxide) electron transfer, bulk electron conduction, Fe(II) release, and phase transformation behavior is emerging, much remains unclear, in part due to poorly interconnected investigations. The focus of this study is on reconciling two mutually similar observations of Fe(II)-catalyzed hematite growth documented spectroscopically and microscopically under substantially different chemical conditions. Here, we employ iron isotopic labeling to demonstrate that hematite grown on the (001) surface in Fe(II)-oxalate solution at pH 2.10 and 348 K has magnetic properties that closely correspond to those of hematite grown in Fe(II) solution at pH 7.4 and room temperature. The temperature evolution and extent of the Morin transition displayed in these two materials strongly suggest a mechanistic link involving trace structural Fe(II) incorporation into the growing hematite. Our findings indicate that Fe(II) catalyzed growth of hematite on hematite can occur under environmentally relevant conditions and may be due to bulk electron conduction previously demonstrated for hematite single crystals.
Details
- Title: Subtitle
- Connecting observations of hematite (alpha-Fe2O3) growth catalyzed by Fe(II)
- Creators
- Kevin M Rosso - Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA. kevin.rosso@pnl.govSvetlana V YaninaChristopher A GorskiPhilip Larese-CasanovaMichelle M Scherer
- Resource Type
- Journal article
- Publication Details
- Environmental science & technology, Vol.44(1), pp.61-67
- DOI
- 10.1021/es901882a
- PMID
- 20039734
- NLM abbreviation
- Environ Sci Technol
- ISSN
- 0013-936X
- eISSN
- 1520-5851
- Publisher
- United States
- Language
- English
- Date published
- 01/01/2010
- Academic Unit
- Civil and Environmental Engineering
- Record Identifier
- 9983992080502771
Metrics
17 Record Views