Savin, S.L.P. and Chadwick, A.V. and O'Dell, L.A. and Smith, M.E. (2007) Characterisation of nanocrystalline magnesium oxide by X-ray absorption spectroscopy. Chemphyschem, 8 (6). pp. 882-889. ISSN 1439-4235 .
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| Official URL http://dx.doi.org/10.1002/cphc.200600750 |
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Abstract
There are numerous methods of preparing nanocrystalline materials. Magnesium oxide is an ideal model system on which to probe the relation of the preparative route and the microstructure. Using X-ray absorption spectroscopy (XAS) we show that the sol-gel route can be used to prepare highly crystalline material provided there is careful control of the calcination conditions. In the present work this is achieved by calcining at high temperatures (at least 800 8C). However, this results in grain growth that can be prevented by the addition of a pinning agent, SiO2, during the preparation of the sol. The pinned samples maintain a particle size of 11 nm even after calcining at 1000 8C. Ball-milling is a common method of preparing nanocrystalline oxides, however the present work shows that this produces a significant fraction of amorphous material, the fraction increasing with decreasing grain size (e.g. 30% for a grain size of 23 nm).
| Item Type: | Article |
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| Uncontrolled keywords: | ball-milling; EXAFS spectroscopy; nanocrystalline oxides; sol-gel processes |
| Subjects: | Q Science > QD Chemistry Q Science > QC Physics |
| Divisions: | Faculties > Science Technology and Medical Studies > School of Physical Sciences > Functional Materials Group |
| Depositing User: | Suzanne Duffy |
| Date Deposited: | 18 Mar 2008 16:47 |
| Last Modified: | 05 Sep 2011 23:27 |
| Resource URI: | http://kar.kent.ac.uk/id/eprint/2294 (The current URI for this page, for reference purposes) |
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