Reduction reactions and densification during in situ TEM heating of iron oxide nanochains

Cecile S. Bonifacio, Gautom Das, Ian M. Kennedy, Klaus Van Benthem

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The reduction reactions and densification of nanochains assembled from γ-Fe2O3 nanoparticles were investigated using in situ transmission electron microscopy (TEM). Morphological changes and reduction of the metal oxide nanochains were observed during in situ TEM annealing through simultaneous imaging and quantitative analysis of the near-edge fine structures of Fe L2,3 absorption edges acquired by spatially resolved electron energy loss spectroscopy. A change in the oxidation states during annealing of the iron oxide nanochains was observed with phase transformations due to continuous reduction from Fe2O3 over Fe3O4, FeO to metallic Fe. Phase transitions during the in situ heating experiments were accompanied with morphological changes in the nanochains, specifically rough-to-smooth surface transitions below 500 °C, neck formation between adjacent particles around 500 °C, and subsequent neck growth. At higher temperatures, coalescence of FeO particles was observed, representing densification.

Original languageEnglish (US)
Article number234303
JournalJournal of Applied Physics
Volume122
Issue number23
DOIs
StatePublished - Dec 21 2017

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densification
iron oxides
transmission electron microscopy
annealing
heating
coalescing
quantitative analysis
phase transformations
metal oxides
energy dissipation
fine structure
electron energy
nanoparticles
oxidation
spectroscopy

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Reduction reactions and densification during in situ TEM heating of iron oxide nanochains. / Bonifacio, Cecile S.; Das, Gautom; Kennedy, Ian M.; Van Benthem, Klaus.

In: Journal of Applied Physics, Vol. 122, No. 23, 234303, 21.12.2017.

Research output: Contribution to journalArticle

Bonifacio, Cecile S. ; Das, Gautom ; Kennedy, Ian M. ; Van Benthem, Klaus. / Reduction reactions and densification during in situ TEM heating of iron oxide nanochains. In: Journal of Applied Physics. 2017 ; Vol. 122, No. 23.
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