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Influence of cobalt ions on the precipitation of goethite in highly alkaline media

Published online by Cambridge University Press:  09 July 2018

S. Krehula  and
S. Musić
S. Krehula*
Affiliation:
Division of Materials Chemistry, Ruđer Bošković Institute, P.O. Box 180, HR-10002 Zagreb, Croatia
S. Musić
Affiliation:
Division of Materials Chemistry, Ruđer Bošković Institute, P.O. Box 180, HR-10002 Zagreb, Croatia
*
*E-mail: [email protected]
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Abstract

The effects of cobalt ions on the precipitation of goethite in highly alkaline media were monitored using X-ray diffraction (XRD), Mössbauer, Fourier transform infrared (FTIR) and energy dispersive X-ray (EDS) spectroscopies and field emission scanning electron microscopy (FESEM) techniques. Tetramethylammonium hydroxide was used as a precipitating agent. The precipitates were collected after heating of the precipitation systems at 160ºC for 2 h. The XRD results showed the formation of goethite structure as a single phase up to r = 6.98 (where r = 100·[Co]/([Co]+[Fe])). Cobalt ferrite was found as an additional phase in the precipitates obtained at r = 9.09 and 13.04. Mössbauer spectroscopy showed the formation of solid solutions of α-(Fe,Co)OOH. The incorporation of cobalt ions into the goethite crystal structure was monitored by a decrease in the average hyperfine magnetic field (⟨Bhf⟩). The value ⟨Bhf⟩ decreased linearly up to r = 5.66, whereas a nonlinear dependence was obtained at r = 6.98 to 13.04. Infrared (IR) bands corresponding to the bending vibrations δOH and γOH were shifted from 892 to 903 cm–1 and from 797 to 800 cm–1, respectively, up to r = 6.98. Fourier transform infrared spectroscopy lacked the sensitivity to monitor the effects of cobalt ions, demonstrated by the Mössbauer analysis. Cobalt incorporation into the crystal structure of goethite induced a gradual elongation of α-(Fe,Co)OOH particles along the crystallographic c axis. The formation of α-(Fe,Co)OOH nanowires was shown at r ⩾6.98. These nanowires were ~700 nm long, whereas their diameter was ~15–20 nm. The majority of the cobalt ferrite particles were in the nanosize range, as observed by FE-SEM. On the basis of the Co/Fe ratio measured by EDS, it appears that the cobalt ferrite particles were not fully stoichiometric.

Keywords

cobalt ionsgoethitecobalt ferriteXRDMössbauerFTIRFE-SEMEDS
Type
Research Article
Information
Clay Minerals , Volume 43 , Issue 1 , March 2008 , pp. 95 - 105
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2008

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References

Balasubramanian, R., Cook, D.C. & Yamashita, M. (2002) Magnetic relaxation in nano-phase chromium substituted goethite. Hyperfine Interactions, 139/140, 167-173.Google Scholar
Cambier (1986) Infrared study of goethites of varying crystallinity and particle size: I. Interpretation of OH and lattice vibration frequencies. Clay Minerals, 21, 191–200.Google Scholar
Cornell, R.M. & Giovanoli, R. (1989) Effect of cobalt on the formation of crystalline iron oxides from ferrihydrite in alkaline media. Clays and Clay Minerals, 37, 65–70.Google Scholar
Cornell, R.M. & Schwertmann, U. (2003) The Iron Oxides, Structure, Properties, Reactions, Occurrence and Uses. Wiley-VCH, Weinheim, Germany, pp. 42–51.Google Scholar
Ferreira, T.A.S., Waerenborgh, J.C., Mendonça, M.H.R.M., Nunes, M.R. & Costa, F.M. (2003) Structural and morphological characterization of FeCo2O4 and CoFe2O4 spinels prepared by a coprecipitation method. Solid State Sciences, 5, 383–392.CrossRefGoogle Scholar
Gerth, J. (1990) Unit-cell dimensions of pure and trace metal-associated goethites. Geochimica et Cosmochimica Acta, 54, 363–371.CrossRefGoogle Scholar
Hisano, S. & Saito, K. (1998) Research and development of metal powder for magnetic recording. Journal of Magnetism and Magnetic Materials, 190, 371–381.Google Scholar
Iwasaki, K. & Yamamura, T. (2002) Whisker-like goethite nanoparticles containing cobalt synthesized in a wet process. Materials Transactions, 43, 2097–2103.Google Scholar
Krehula, S., Popović, S. & Musić, S. (2002) Synthesis of acicular a-FeOOH particles at a very high pH. Materials Letters, 54, 108–113.CrossRefGoogle Scholar
Krehula, S., Musić, S., Skoko, Z. & Popović, S. (2006) The influence of Zn-dopant on the precipitation of α-FeOOH in highly alkaline media. Journal of Alloys and Compounds, 420, 260–268.CrossRefGoogle Scholar
Mohapatra, M., Anand, S., Das, R.P., Upadhyay, C. & Verma, H.C. (2002) Preparation and characterization of Cu(II), Ni(II) or Co(II) ion-doped goethite samples and their conversion to magnetite in NH3-FeSO4-H2O medium. Hydrometallurgy, 66, 125–134.Google Scholar
Morales, M.P., Walton, S.A., Prichard, L.S., Serna, C.J., Dickson, D.P.E. & O’Grady, K. (1998) Characterisation of advanced metal particle recording media pigments. Journal of Magnetism and Magnetic Materials, 190, 357–370.Google Scholar
Mørup, S., Madsen, M.B., Franck, J., Villadsen, J. & Koch, C.J.W. (1983) A new interpretation of Mössbauer spectra of microcrystalline goethite: “super-ferromagnetism” or “super-spin-glass” behaviour. Journal of Magnetism and Magnetic Materials, 40, 163–174.CrossRefGoogle Scholar
Murad, E. (1982) The characterization of goethite by Mössbauer spectroscopy. American Mineralogist, 67, 1007–1011.Google Scholar
Murad, E. & Bowen, L.H. (1987) Magnetic ordering in Al-rich goethites: Influence of crystallinity. American Mineralogist, 72, 194–200.Google Scholar
Murad, E. & Johnston, J.H. (1987) Iron oxides and oxyhydroxides. Pp. 507–582 in: Mössbauer Spectroscopy Applied to Inorganic Chemistry (Long, G.H., editor). Plenum Press, New York.Google Scholar
Murad, E. & Schwertmann, U. (1983) The influence of aluminium substitution and crystallinity on the Mössbauer spectra of goethite. Clay Minerals, 18, 301–312.CrossRefGoogle Scholar
Sawatzky, G.A., van der Woude, F. & Morrish, A.H. (1968) Cation distributions in octahedral and tetrahedral sites of the ferrimagnetic spinel CoFe2O4 . Journal of Applied Physics, 39, 1204–1205.Google Scholar
Sawatzky, G.A., van der Woude, F. & Morrish, A.H. (1969) Mössbauer study of several ferrimagnetic spinels. Physical Review, 187, 747–757.CrossRefGoogle Scholar
Sharrock, M.P. & Bodnar, R.E. (1985) Magnetic materials for recording: An overview with special emphasis on particles. Journal of Applied Physics, 57, 3919–3924.CrossRefGoogle Scholar
Sudakar, C., Subbanna, G.N. & Kutty, T.R.N. (2004) Effect of cationic substituents on particle morphology of goethite and the magnetic properties of maghemite derived from substituted goethite. Journal of Materials Science, 39, 4271–4286.Google Scholar
Verdonck, L., Hoste, S., Roelandt, F.F. & van der Kelen, G.P. (1982) Normal coordinate analysis of α-FeOOH - a molecular approach. Journal of Molecular Structure, 79, 273–279.CrossRefGoogle Scholar