Cation distribution in nanocrystalline ZnFe2O4 investigated using x-ray absorption fine structure spectroscopy

Physics Division, PINSTECH, PO Nilore, Islamabad, Pakistan.
Journal of Physics Condensed Matter (Impact Factor: 2.35). 10/2009; 21(40):405303. DOI: 10.1088/0953-8984/21/40/405303
Source: PubMed


X-ray absorption fine structure (XAFS) spectroscopy has been employed to investigate the cation distribution in nanocrystalline zinc ferrites (ZnFe(2)O(4)), synthesized in acidic and basic media at different temperatures. By using (Zn(1-x)Fe(x))[Ni(x)Fe(2-x)]O(4) as model compounds we have determined cation distribution in nanosize ZnFe(2)O(4). The cation distribution for samples synthesized at low temperature (400 °C) is (Zn(0.5)Fe(0.5))[Zn(0.5)Fe(1.5)]O(4) for urea- and (Zn(0.75)Fe(0.25))[Zn(0.25)Fe(1.75)]O(4) for citric-acid-based samples. These results show that samples synthesized at and above 600 °C have a local structural environment identical to that of bulk ZnFe(2)O(4).

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