Influence of Zinc Doping on the Structural and Magnetic Properties of α-Fe2O3

• Published in: Journal of solid state chemistry Vol. 156; no. 2; pp. 408 - 414
• Main Authors: Ayub, Ibrar, Berry, Frank J., Bilsborrow, Robert L., Helgason, Örn, Mercader, Roberto C., Moore, Elaine A., Stewart, Silvana J., Wynn, Paul G.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.02.2001; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Defects and impurities in crystals; microstructure; Doping and impurity implantation in other materials; Exact sciences and technology; Inorganic compounds; Magnetic resonances and relaxations in condensed matter, mössbauer effect; Mossbauer effect; other γ-ray spectroscopy; Mössbauer effect; other γ-ray spectroscopy; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; Water, oxides, hydroxides, peroxides; Hyperfine magnetic field; Moessbauer effect; Inorganic compounds; Phase transformations; Zinc additions; Transition element compounds; Crystal chemistry; Experimental study; Temperature range 273-400 K; Crystal doping; EXAFS; Temperature range 400-1000 K; Alpha form; Zinc oxides; Ferrites spinels; Substitutional impurities; Temperature effects; Iron oxides
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1006/jssc.2000.9014

Zinc-doped α-Fe2O3 has been prepared by hydrothermal methods. The zinc K-edge EXAFS and interatomic potential calculations indicate that Zn2+ ions substitute for Fe3+ ions in the lattice and are accompanied by oxygen vacancies. The 57Fe Mössbauer spectra recorded between 296 and 18 K demonstrate that the Morin transition in α-Fe2O3 is completely suppressed within this temperature range by the presence of zinc. The 57Fe Mössbauer spectra recorded in situ at temperatures between 300 and 915 K show the material to undergo conversion to the spinel-related ZnFe2O4 phase in this temperature regime. The results demonstrate that the structural and magnetic properties of zinc-doped α-Fe2O3 and its behavior at elevated temperatures are different from those of magnesium-doped α-Fe2O3.