Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1517375 | Journal of Physics and Chemistry of Solids | 2010 | 4 Pages |
Abstract
Phase transition and bulk moduli of bulk and nanocrystalline γ-Fe2O3 were studied using synchrotron X-ray diffraction under high pressure. Contrary to most other nanomaterials, nanocrystalline γ-Fe2O3 begins to transform into α-Fe2O3 at the same pressure as bulk γ-Fe2O3, which is caused by a special structure of γ-Fe2O3, in which there exist vacancies of crystal. It is believed that phase transition starts from a certain site of vacancy because of the stress concentration at vacancy sites. Compared to bulk material, nanocrystalline γ-Fe2O3 has a larger bulk modulus, which is ascribed to the large ratio of surface to volume.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Hongyang Zhu, Yanzhang Ma, Haibin Yang, Cheng Ji, Dongbin Hou, Lingyun Guo,