Journal article
Nano size crystals of goethite, alpha-FeOOH: Synthesis and thermal transformation
Electroceramics, Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark1
Fuel Cells and Solid State Chemistry Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark2
Risø National Laboratory for Sustainable Energy, Technical University of Denmark3
An aqueous suspension of amorphous iron(III) hydroxide was kept at room temperature (298K) for 23 years. During this period of time the pH of the liquid phase changed from 4.3 to 2.85, and nano size crystals of goethite, α-FeOOH crystallised from the amorphous iron(III) hydroxide. Transmission electron microscopy (TEM) investigations, Mossbauer spectra, and powder X-ray diffraction using Co Kα radiation showed that the only iron containing crystalline phase present in the recovered product was α-FeOOH.
The size of these nano particles range from 10 to 100nm measured by TEM. The thermal decomposition of α-FeOOH was investigated by time-resolved in situ synchrotron radiation powder X-ray diffraction and the data showed that the sample of α-FeOOH transformed to α-Fe2O3 in the temperature range 444-584K.
A quantitative phase analysis shows the increase in scattered X-ray intensity from α-Fe2O3 to follow the decrease of intensity from α-FeOOH in agreement with the topotactic phase transition.
Language: | English |
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Year: | 2007 |
Pages: | 1431-1435 |
ISSN: | 1095726x and 00224596 |
Types: | Journal article |
DOI: | 10.1016/j.jssc.2007.01.032 |
ORCIDs: | Bahl, Christian Robert Haffenden |