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EPR of VO2+ ions in Al-pillared montmorillonite

Published online by Cambridge University Press:  09 July 2018

O. Braddell ,
R. C. Barklie  and
D. H. Doff
O. Braddell
Affiliation:
Physics Department, Trinity College, Dublin 2, Ireland
R. C. Barklie
Affiliation:
Physics Department, Trinity College, Dublin 2, Ireland
D. H. Doff
Affiliation:
Geology Department, Trinity College, Dublin 2, Ireland
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Abstract

A pillared smectite clay has been formed by treating Na-montmorillonite with a hydroxy-aluminium solution with an OH/Al ratio of two. Heating the pillared clay for four h at 500°C reduces the interlayer spacing, measured at ambient humidity, from ∼ 9·4 to 8·0 Å. Hydrated VO2+ (and Mg2+) ions have been introduced into the region between the pillars by immersing the pillared clay in VOSO4-MgCl2 solutions and EPR measurements show that in general both immobile and mobile VO2+ ions are present. The immobile ion is probably VO2+(OH)x(H2O)5·x where x = 2–4, and is adsorbed on the pillars with a concentration that saturates at about 1 per 8 Al13 pillars in the unfired clay, and 1 per 4·3 pillars in the fired clay. The mobile species is VO2+(H2O)5 and for both fired and unfired clay in the wet state at room temperature it has a rotational correlation time of (9 ± 1) × 10−11s rad−1.

Type
Research Article
Information
Clay Minerals , Volume 25 , Issue 1 , March 1990 , pp. 15 - 25
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1990

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References

Abragam, A. & Bleaney, B. (1970) Electron Paramagnetic Resonance of Transiton Ions, p. 175. Clarendon, Oxford.Google Scholar
Atkins, P.W. & Kivelson, D. (1966) ESR linewidths in solution. II. Analysis of spin-rotational data. J. Chem. Phys., 44, 169–174.CrossRefGoogle Scholar
Barklie, R.C., Girard, O. & Braddell, O. (1988) EPR of VO2+ in a Nafion membrane. J. Phys. Chem., 92, 1371–1377.Google Scholar
Braddell Barklie, R.C., Doff, D.H., Gangas, N.H.J. & McKimm, A. (1987) EPR ofCu22+ ions in pillared clay. Zeit. fur Physik. Chem., 151, 157–164.Google Scholar
Brindley, G.W. & Sempels, R.E. (1977) Preparation and properties of some hydroxy-aluminium beidellites. Clay Miner., 12, 229–236.CrossRefGoogle Scholar
Chasteen, M.D. & Hanna, M.V. (1972) Electron paramagnetic resonance line widths of vanadyl (IV) x- hydroxycarboxylates. J. Phys. Chem., 76, 3951–3957.Google Scholar
Clementz, D.M., Pinnavaia, T.J. & Mortland, M.M. (1973) Stereochemistry of hydrated copper (II) ions on the interlamellar surfaces of layer silicates. An electron spin resonance study. J. Phys. Chem., 77, 196–200.Google Scholar
Kon, H. & Sharpless, N.E. (1966) Electron Spin Resonance study of some halomolybendyl, -tungstenyl and -vanadyl complexes in solution. J. Phys. Chem., 70, 105–111.CrossRefGoogle Scholar
Lahav, N., Shani, U. & Shabtai, J. (1978) Cross-linked smectites. I. Synthesis and properties of hydroxy- aluminum montmorillonite. Clays Clay Miner., 26, 107–115.Google Scholar
Martini, G., Ottaviani, M.F. & Seravalli G .(1975) Electron spin resonance study of Vanadyl complexes adsorbed on synthetic zeolites. J. Phys. Chem., 79, 1716–1720.Google Scholar
McBride, M.B. (1979) Mobility and reactions of VO2+ on hydrated smectite surfaces. Clays Clay Miner., 27, 91–96.Google Scholar
Pinnavaia, T.J., Tzou, M., Landau, S.D. & Raythatha, R.H. (1984) On the pillaring and delamination of smectite clay catalysts by polyoxo cations of aluminium. J. Mol. Catal., 27, 195–212.Google Scholar
Plee, D., Borg, F., Gatineau, L. & Fripiat, J.J. (1985) High-resolution solid state 27Al and 29Si nuclear magnetic resonance study of pillared clays. J. Am. Chem. Soc., 107, 2362–2369.Google Scholar
Tennakckdn, D.T.B., Jones, W. & Thomas, J.M. (1986) Structural aspects of metal-oxide-pillared sheet silicates. J. Chem. Soc. Faraday Trans., 1, 82, 3081–3095.Google Scholar
Van Olphen, H. & Fripiat, J.J. (1979) Data Handbook for Clay Minerals and other Non-Metallic Minerals. Pergamon Press, Oxford.Google Scholar
Wilson, R. & Kivelson, D. (1966) ESR linewidths in solution. I. Experiments on antisotropic and spin-rotational effects. J. Chem. Phys. 44, 154–168.Google Scholar