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Title: Magnetic diphase nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3}

Abstract

Magnetic diphase nanostructures of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3} were synthesized by a solvothermal method. The formation reactions were optimized by tuning the initial molar ratios of Fe/Zn. All samples were characterized by X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, and Raman spectra. It is found that when the initial molar ratio of Fe/Zn is larger than 2, a diphase magnetic nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3} was formed, in which the presence of ZnFe{sub 2}O{sub 4} enhanced the thermal stability of {gamma}-Fe{sub 2}O{sub 3}. Further increasing the initial molar ratio of Fe/Zn larger than 6 destabilized the diphase nanostructure and yielded traces of secondary phase {alpha}-Fe{sub 2}O{sub 3}. The grain surfaces of diphase nanostructure exhibited a spin-glass-like structure. At room temperature, all diphase nanostructures are superparamagnetic with saturation magnetization being increased with {gamma}-Fe{sub 2}O{sub 3} content. - Graphical abstract: Spherical diphase nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3} was obtained by varying the initial molar ratio of Fe/Zn.

Authors:
 [1];  [1];  [1];  [2];  [3]
  1. State Key Structural Chemistry Laboratory and Fujian Institute of Research on the Structure of Matter, Graduate School of Chinese Academy of Sciences, Fuzhou 350002 (China)
  2. Department of Physics, Jilin University, Changchun 130023 (China)
  3. State Key Structural Chemistry Laboratory and Fujian Institute of Research on the Structure of Matter, Graduate School of Chinese Academy of Sciences, Fuzhou 350002 (China), E-mail: lipingli@fjirsm.ac.cn
Publication Date:
OSTI Identifier:
21015744
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 180; Journal Issue: 3; Other Information: DOI: 10.1016/j.jssc.2006.12.034; PII: S0022-4596(07)00014-X; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION SPECTROSCOPY; INFRARED SPECTRA; IRON OXIDES; MAGNETIZATION; NANOSTRUCTURES; RAMAN SPECTRA; SPIN GLASS STATE; SUPERPARAMAGNETISM; TEMPERATURE RANGE 0273-0400 K; THERMAL GRAVIMETRIC ANALYSIS; X-RAY DIFFRACTION; ZINC COMPOUNDS

Citation Formats

Bo Xiangxi, Li Guangshe, Qiu Xiaoqing, Xue Yanfeng, and Li Liping. Magnetic diphase nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3}. United States: N. p., 2007. Web.
Bo Xiangxi, Li Guangshe, Qiu Xiaoqing, Xue Yanfeng, & Li Liping. Magnetic diphase nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3}. United States.
Bo Xiangxi, Li Guangshe, Qiu Xiaoqing, Xue Yanfeng, and Li Liping. Thu . "Magnetic diphase nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3}". United States. doi:.
@article{osti_21015744,
title = {Magnetic diphase nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3}},
author = {Bo Xiangxi and Li Guangshe and Qiu Xiaoqing and Xue Yanfeng and Li Liping},
abstractNote = {Magnetic diphase nanostructures of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3} were synthesized by a solvothermal method. The formation reactions were optimized by tuning the initial molar ratios of Fe/Zn. All samples were characterized by X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, and Raman spectra. It is found that when the initial molar ratio of Fe/Zn is larger than 2, a diphase magnetic nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3} was formed, in which the presence of ZnFe{sub 2}O{sub 4} enhanced the thermal stability of {gamma}-Fe{sub 2}O{sub 3}. Further increasing the initial molar ratio of Fe/Zn larger than 6 destabilized the diphase nanostructure and yielded traces of secondary phase {alpha}-Fe{sub 2}O{sub 3}. The grain surfaces of diphase nanostructure exhibited a spin-glass-like structure. At room temperature, all diphase nanostructures are superparamagnetic with saturation magnetization being increased with {gamma}-Fe{sub 2}O{sub 3} content. - Graphical abstract: Spherical diphase nanostructure of ZnFe{sub 2}O{sub 4}/{gamma}-Fe{sub 2}O{sub 3} was obtained by varying the initial molar ratio of Fe/Zn.},
doi = {},
journal = {Journal of Solid State Chemistry},
number = 3,
volume = 180,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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