Synthesis and properties of iridium-doped hematite (α-Fe2O3)

被引:41
作者
Krehula, Stjepko [1 ]
Stefanic, Goran [1 ]
Zadro, Kreso [2 ]
Krehula, Ljerka Kratofil [3 ]
Marcius, Marijan [1 ]
Music, Svetozar [1 ]
机构
[1] Rudjer Boskovic Inst, Div Mat Chem, HR-10002 Zagreb, Croatia
[2] Univ Zagreb, Fac Sci, Dept Phys, Zagreb 10000, Croatia
[3] Univ Zagreb, Fac Chem Engn & Technol, Zagreb 10000, Croatia
关键词
Hematite; Iridium; Morin transition; Fe-57; Mossbauer; UV-Vis-NIR; FE-57; MOSSBAUER-SPECTROSCOPY; HIGHLY ALKALINE MEDIA; X-RAY-DIFFRACTION; MORIN TRANSITION; SUBSTITUTED HEMATITE; MAGNETIC-PROPERTIES; OPTICAL-PROPERTIES; ALPHA-FEOOH; IRON-OXIDES; STRUCTURAL-CHARACTERIZATION;
D O I
10.1016/j.jallcom.2012.08.009
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
The effect of the incorporation of Ir3+ ions on the properties of alpha-Fe2O3 formed by dehydroxylation of alpha-FeOOH was investigated using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Fe-57 Mossbauer, UV-Vis-NIR and FT-IR spectroscopies, SQUID magnetometer, field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS). Pure and Ir-doped hematite samples were obtained by heating of pure and Ir-doped goethites (alpha-FeOOH) formed by precipitation from mixed Fe(III)-Ir(III) chloride solutions in a highly alkaline medium. The incorporation of Ir3+ ions into the alpha-Fe2O3 structure led to changes in unit-cell dimensions, crystallinity, particle size and shape, as well as changes in the magnetic, infrared and UV-Vis properties. An increase in the temperature of the Morin transition with an increase in It-doping was observed by Mossbauer spectroscopy and magnetic measurements. (c) 2012 Elsevier B.V. All rights reserved.
引用
收藏
页码:200 / 209
页数:10
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