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Characterization of Nanocrystalline γ–Fe2O3 Prepared by Wet Chemical Method

Published online by Cambridge University Press:  31 January 2011

G. Ennas*
Affiliation:
Dipartimento di Scienze Chimiche, Universitá degli studi di Cagliari, Via Ospedale 72, I-09124 Cagliari, Italy
G. Marongiu
Affiliation:
Dipartimento di Scienze Chimiche, Universitá degli studi di Cagliari, Via Ospedale 72, I-09124 Cagliari, Italy
A. Musinu
Affiliation:
Dipartimento di Scienze Chimiche, Universitá degli studi di Cagliari, Via Ospedale 72, I-09124 Cagliari, Italy
A. Falqui
Affiliation:
Consorzio Promea, V.le R.Margherita 30, I-09124 Cagliari, Italy
P. Ballirano
Affiliation:
Dipartimento di Chimica, Istituto Nazionale di Fisica della Materia, Universitá degli studi di Roma “La Sapienza, ” P.le A.Moro 5, I-00185 Roma, Italy
R. Caminiti
Affiliation:
Dipartimento di Chimica, Istituto Nazionale di Fisica della Materia, Universitá degli studi di Roma “La Sapienza, ” P.le A.Moro 5, I-00185 Roma, Italy
*
a)Address all correspondence to this author. e-mail: ennas@vaxca1.unica.it
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Abstract

Homogeneous maghemite (γ–Fe2O3) nanoparticles with an average crystal size around 5 nm were synthesized by successive hydrolysis, oxidation, and dehydration of tetrapyridino-ferrous chloride. Morphological, thermal, and structural properties were investigated by transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and x-ray diffraction (XRD) techniques. Rietveld refinement indicated a cubic cell. The superstructure reflections, related to the ordering of cation lattice vacancies, were not detected in the diffraction pattern. Kinetics of the solid-state phase transition of nanocrystalline maghemite to hematite (α–Fe2O3), investigated by energy dispersive x-ray diffraction (EDXRD), indicates that direct transformation from nanocrystalline maghemite to microcrystalline hematite takes place during isothermal treatment at 385 °C. This temperature is lower than that observed both for microcrystalline maghemite and for nanocrystalline maghemite supported on silica.

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Articles
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

1.Kryder, M.H., MRS Bulletin 21 (9), 17 (1996).CrossRefGoogle Scholar
2.Onodera, S., Kondo, H., and Kawana, T., MRS Bulletin 21 (9), 35 (1996).CrossRefGoogle Scholar
3.Watanabe, H. and Seto, J., Bull. Chem. Soc. Jpn. 61, 2411 (1991).CrossRefGoogle Scholar
4.Hong, F., Yang, B.L., Schwartz, L. H., and Kung, H. H., J. Phys. Chem. 88, 2525 (1984).CrossRefGoogle Scholar
5.Kroll, E., Winnik, F. M., and Ziolo, R., Chem. Mater. 8, 1594 (1996).CrossRefGoogle Scholar
6.Vollath, D., Szabo, D. V., Taylor, R. D., Willis, J. O., and Sickafus, K. E., Nanostruct. Mater. 6, 941 (1995).CrossRefGoogle Scholar
7.Tronc, F., Prene, P., Jolivet, J. P., d'Orazio, F., Lucari, F., Fiorani, D., Godinho, M., Cherkaoui, R., Nogues, M., and Dormann, J.L., Hyperfine Interact. 95, 129 (1995).CrossRefGoogle Scholar
8.Linderoth, S., Hendriksen, P., Bodker, F., Wells, S., Davies, K., Charles, S. W., and Morup, S., J. Appl. Phys. 75, 6583 (1994).CrossRefGoogle Scholar
9.Chadwick, J. C., Jones, D. H., Thomas, M.F., Tatlock, C.J., and Devenish, M., Hyperfine Interact. 28, 541 (1986).CrossRefGoogle Scholar
10.Kang, Y.S., Risbud, S., Rabolt, J.F., and Stroeve, P., Chem. Mater. 8, 2209 (1996).CrossRefGoogle Scholar
11.Ziolo, R.F., Giannelis, E.P., Weinstein, B. A., O'Horo, M. P., Ganguly, B.N., Mehrotra, V., Russel, M.W., and Huffman, D. R., Science 257, 219 (1992).CrossRefGoogle Scholar
12.Morales, M.P., Pecharroman, C., Gonzáles Carreño, T., and Serna, C. J., J. Solid State Chem. 108, 158 (1994).CrossRefGoogle Scholar
13.Ayyub, P., Multani, M., Barma, M., and Viiayaraghavan, R., J. Phys. C 21, 2229 (1988).CrossRefGoogle Scholar
14.Takahashi, N., Kakuta, N., Ueno, A., Yamaguchi, K., Fujii, T., Mizushima, T., and Udagawa, Y., J. Mater. Sci. 26, 497 (1991).CrossRefGoogle Scholar
15.Ennas, G., Musinu, A., Piccaluga, G., Zedda, D., Gatteschi, D., Sangregorio, C., Stanger, J. L., Concas, G., and Spano, G., Chem. Mater. 10, 495 (1998).CrossRefGoogle Scholar
16.Tronc, E. and Jolivet, J. P., Hyperfine Interact. 28, 525 (1986).CrossRefGoogle Scholar
17.Tronc, E., Jolivet, J. P., and Livage, J., Hyperfine Interact. 54, 737 (1990).CrossRefGoogle Scholar
18.Haneda, K. and Morrish, A. H., Solid State Commun. 22, 779 (1977).CrossRefGoogle Scholar
19.Baudisch, O. and Hartung, W.H., Inorg. Synth. 1, 184 (1939).CrossRefGoogle Scholar
20.Baudisch, O. and Hartung, W.H., Inorg. Synth. 1, 185 (1939).CrossRefGoogle Scholar
21.Snell, F. D. and Ettre, L. S., in Encyclopedia of Industrial Chemical Analysis (Wiley, New York, 19701972).Google Scholar
22.Flaschka, H.A., in EDTA Titrations (Pergamon Press, London, U.K., 1959), p. 81.Google Scholar
23.Warren, B.E., in X-Ray Diffraction (Addison-Wesley, Reading, MA, 1968).Google Scholar
24.Rietveld, H. M., J. Appl. Crystallogr. 2, 65 (1969).CrossRefGoogle Scholar
25.Von Dreel, R.B. and Larson, A. C., in LANSCE Newsletter no. 4, Los Alamos, NM Winter 1988.Google Scholar
26.Howard, C. J., J. Appl. Crystallogr. 15, 615 (1982).CrossRefGoogle Scholar
27.Carbone, M., Caminiti, R., and Sadun, C., J. Mater. Chem. 6, 1709 (1996).CrossRefGoogle Scholar
28.Caminiti, R., Sadun, C., Bionducci, M., Buffa, F., Ennas, G., Licheri, G., Musinu, A., and Navarra, G., Gazz. Chim. Ital. 127, 59 (1997).Google Scholar
29.JCPDF card no. 8–98 and no. 8–524, International Center for Diffraction Data, Swarthmore, PA.Google Scholar
30.Klug, H.P. and Alexander, L. E., in X-Ray Diffraction Procedures for Polycrystalline Materials (John Wiley & Sons, New York, 1974).Google Scholar
31.Greaves, C., J. Solid State Chem. 49, 325 (1983).CrossRefGoogle Scholar
32.Shmakov, A. N., Kryukova, G. N., Tsybhulya, V. S., Chiuviliu, A.L., and Solovyeva, V. P., J. Appl. Crystallogr. 28, 141 (1995).CrossRefGoogle Scholar
33.Wells, A. F., in Structural Inorganic Chemistry (Oxford Univ. Press, London, 1975).Google Scholar
34.Haas, C., J. Phys. Chem. Solids 26, 1225 (1965).CrossRefGoogle Scholar
35.Chhabra, V., Ayyub, P., Chattopadhyay, S., and Maitra, A. N., Mater. Lett. 26, 21 (1996).CrossRefGoogle Scholar
36.Kachi, S., Momiyama, K., and Shimizu, S., J. Phys. Soc. Jpn. 18, 1 (1963).Google Scholar
37.Torrès Sánchez, R. M., J. Mater. Sci. Lett. 15, 461 (1996).CrossRefGoogle Scholar
38.Schumaker, S., Birringer, R., Strauss, R., and Gleiter, H., Acta Metall. 37, 2485 (1989).CrossRefGoogle Scholar
39.Goldsmith, A. N., Echer, C. M., and Alivisatos, A. P., Science 256, 1425 (1992).Google Scholar
40.Perkins, D. A. and Attfield, J. P., J. Chem. Soc. Chem. Commun. 1991, 229 (1991).CrossRefGoogle Scholar
41.Avrami, M., J. Chem. Phys. 7, 1103 (1939) and 8, 212 (1940).CrossRefGoogle Scholar
42.Meillon, S., Dammak, H., Flaving, E., and Pascard, H., Philos. Mag. 72, 105 (1995).Google Scholar
43.Oosterhout, G. W., Acta Crystallogr. 13, 932 (1960).CrossRefGoogle Scholar
44.Ivanov, P. and Mokhov, M., J. Magn. Magn. Mater. 104–107, 417 (1992).CrossRefGoogle Scholar