1. An X-ray absorption spectroscopy study of the inversion degree in zinc ferrite nanocrystals dispersed on a highly porous silica aerogel matrix.
- Author
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Carta, D., Marras, C., Loche, D., Mountjoy, G., Ahmed, S. I., and Corrias, A.
- Subjects
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X-ray spectroscopy , *ZINC ferrites , *CRYSTAL structure , *NANOPARTICLES , *NANOCRYSTALS , *POROUS silica , *AEROGELS , *PARTICLE size distribution - Abstract
The structural properties of zinc ferrite nanoparticles with spinel structure dispersed in a highly porous SiO2 aerogel matrix were compared with a bulk zinc ferrite sample. In particular, the details of the cation distribution between the octahedral (B) and tetrahedral (A) sites of the spinel structure were determined using X-ray absorption spectroscopy. The analysis of both the X-ray absorption near edge structure and the extended X-ray absorption fine structure indicates that the degree of inversion of the zinc ferrite spinel structures varies with particle size. In particular, in the bulk microcrystalline sample, Zn2+ ions are at the tetrahedral sites and trivalent Fe3+ ions occupy octahedral sites (normal spinel). When particle size decreases, Zn2+ ions are transferred to octahedral sites and the degree of inversion is found to increase as the nanoparticle size decreases. This is the first time that a variation of the degree of inversion with particle size is observed in ferrite nanoparticles grown within an aerogel matrix. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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