Investigation of the precursors of γ-Fe2O3 in Fe2O3/SiO2 nanocomposites obtained through sol-gel

被引:35
作者
Cannas, C
Concas, G
Falqui, A
Musinu, A [1 ]
Spano, G
Piccaluga, G
机构
[1] Univ Monserrato, Dipartimento Sci Chim, I-09042 Monserrato, CA, Italy
[2] Univ Monserrato, Dipartimento Fis, I-09042 Monserrato, CA, Italy
[3] Cittadella Univ, INFM, I-09042 Monserrato, CA, Italy
关键词
D O I
10.1016/S0022-3093(01)00504-X
中图分类号
TQ174 [陶瓷工业]; TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
The structure and the magnetic properties of a series of Fe2O3-SiO2 nanocomposites (16.9 and 28.5 wt% of Fe2O3/(Fe2O3 + SiO2)), prepared by a sol-gel method and submitted to thermal treatments in a temperature range 300-700 degreesC, were investigated through X-ray diffraction (XRD), transmission electron microscopy (TEM), Mossbauer spectroscopy and magnetometry. Poorly crystallized particles, belonging to the 2-line ferrihydrite phase, were found in all the samples and recognized as precursors of the gamma -Fe2O3 that form in Fe2O3-SiO2 nanocomposites at T > 700 degreesC. The result was achieved through a detailed comparison of structural and magnetic properties of nanocomposites with a bulk iron (III) oxide hydrated reference sample. (C) 2001 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:64 / 73
页数:10
相关论文
共 32 条
  • [1] SIZE-INDUCED STRUCTURAL PHASE-TRANSITIONS AND HYPERFINE PROPERTIES OF MICROCRYSTALLINE FE2O3
    AYYUB, P
    MULTANI, M
    BARMA, M
    PALKAR, VR
    VIJAYARAGHAVAN, R
    [J]. JOURNAL OF PHYSICS C-SOLID STATE PHYSICS, 1988, 21 (11): : 2229 - 2245
  • [2] BROOKS JS, 1992, PHYS CHEM GLASSES, V33, P1767
  • [3] IR and NMR study of nanoparticle-support interactions in a Fe2O3-SiO2 nanocomposite prepared by a sol-gel method
    Bruni, S
    Cariati, F
    Casu, M
    Lai, A
    Musinu, A
    Piccaluga, G
    Solinas, S
    [J]. NANOSTRUCTURED MATERIALS, 1999, 11 (05): : 573 - 586
  • [4] Formation of cubic phases on heating ferrihydrite
    Campbell, AS
    Schwertmann, U
    Campbell, PA
    [J]. CLAY MINERALS, 1997, 32 (04) : 615 - 622
  • [5] Superparamagnetic behaviour of γ-Fe2O3 nanoparticles dispersed in a silica matrix
    Cannas, C
    Concas, G
    Gatteschi, D
    Falqui, A
    Musinu, A
    Piccaluga, G
    Sangregorio, C
    Spano, G
    [J]. PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 2001, 3 (05) : 832 - 838
  • [6] Structural and magnetic properties of Fe2O3 nanoparticles dispersed over a silica matrix
    Cannas, C
    Gatteschi, D
    Musinu, A
    Piccaluga, G
    Sangregorio, C
    [J]. JOURNAL OF PHYSICAL CHEMISTRY B, 1998, 102 (40): : 7721 - 7726
  • [7] MOSSBAUER-SPECTRA OF FERRIHYDRITE - SUPERFERROMAGNETIC INTERACTIONS AND ANISOTROPY LOCAL ENERGY
    CIANCHI, L
    MANCINI, M
    SPINA, G
    TANG, H
    [J]. JOURNAL OF PHYSICS-CONDENSED MATTER, 1992, 4 (08) : 2073 - 2077
  • [8] Cornell R. M., 1996, IRON OXIDES STRUCTUR, p[14, 38, 59, 95, 118, 129, 148, 291, 352, 401, 434, 489]
  • [9] Cornell R M, 1996, IRON OXIDES STRUCTUR, P120
  • [10] CORNELL RM, 1996, IRON OXIDES STRUCTUR, P361