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Systematic Preparation Of Polyoxometalate Pillared Layered Double Hydroxides Via Direct Aqueous Reaction

  • Jiandang Wang (a1), Ying Tian (a1), Ren-Chain Wang (a1), Jorge L. Colón (a1) and Abraham Clearfield (a1)...


The series of layered double hydroxides, Mg n Al(OH)2n+2 X (n = 2–5, X = NO3 or Cl) and Ni n Al(OH) 2n+2 X (n = 2–4, X = NO3 or Cl), were pillared with polyoxometalate ions of the Keggin structure, ranging from [PW12O40]3− to [PV4W8O40]7−, in aqueous solution. Full exchange of the Keggin ions into the layers is achieved as evidenced by X-ray powder diffraction, infrared spectroscopy, elemental analysis and thermogravimetric analysis. Also, partial exchange was observed for Ni5Al(OH)12NO3 The key factor that effects these reactions is the pre-swelling step. Thus, when the layered double hydroxides are thoroughly wet either by preparing wet solids or by soaking the dried products for an extended period, pillaring reactions proceed with great ease. Relations can be extracted between the water content and the separation between the layers, as well as between layer charge density and the charge of the Keggin ion. The pillared layered double hydroxides were found generally to have interlayer distances ranging from 11.0 to 13.5 Å, which is smaller than the numerical sum of the Keggin ion diameter and the ideal thickness of the hydroxide layer. This fact and the low crystallinity are attributed to strong interaction between the basic layered double hydroxides and the acidic Keggin ions. A more crystalline phase with the expected 14.5 Å interlayer spacing was also obtained as a mixture with the lower spaced products.



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1. Vaughan, D.E.W., Catal. Today 2, 187 (1988).
2. Catalysis Today - Pillared Clays edited by Burch, R. (Elsevier, Amsterdam, 1988) Vol.2, pp 199295.
3. Figueras, F., Catal. Rev. Sci. Eng. 30, 457 (1988).
4. Adams, J.M., Appl. Clay Sci. 2, 309 (1987).
5. Cataylsis Today - Pillared Clays. edited by Burch, R. (Elsevier, Amsterdam,1988) Vol.2, pp 297355.
6. Clearfield, A. and Roberts, B.D., Inorg. Chem. 27, 3237 (1988).
7. Cheng, S. and Wang, T.-C., Inorg. Chem., 28 1283 1989).
8. Jones, W. and Chibwe, M., in Pillared Layered Structures edited by Mitchell, I.V. (Elsevier, London, 1990) pp 6777.
9. Allmann, R., Chimia 27, 4628 (1970).
10. Drezdzon, M.A., Inorg. Chem. 227, 4628 (1988).
11. Kwon, T. and Pinnavaia, T.J., Chem. Mater. 1, 381(1989).
12. Dimotakis, E.D. and Pinnavaia, T.J., Inorg. Chem. 29 2393 (1990).
13. Shriver, D.F. and Drezdzon, M.A., The Manipulation of Air-Sensitive Compounds, 2nd ed. (Wiley, New York, 1986).
14. Pope, M.T., Heteropoly and Isopoly Oxometalates (Springer-Verlag, New York, 1983).
15. (a) Domaille, P.J. and Watunya, G., Inorg. Chem., 25 1239 (1986). (b) D.P. Smith and M.T. Pope, Inorg. Chem. 12, 331(1973).
16. (a) Pope, M.T. and Varga, G.M. Jr.,, Inorg. Chem. 5, 1249 (1960). (b) H. Wu, J. Biol. Chem., 43, 189 (1920).
17. Clearfield, A., Kieke, M., Kwan, J., Colón, J.L. and Wang, R.-C., J. Inclusion Phenom., submitted.
18. Wang, R.-C. and Clearfield, A., Patent pending and manuscript in preparation.
19. In one experiment with highly crystalline Mg2AI(OH)6CI, our colleague Shea, W.-L. obtained a series of XPD patterns during the process of slow air drying of the wet sample. Very sharp reflections were observed at both d = 15.0,Å and 9.0 Å on the first, wettest sample.
20. Theng, B.K.G., The Chemistry of Clay-Organic Reactions (Wiley, New York, 1974).
21. An error is obvious in reference 11 in which Kwon and Pinnavaia claimed that “for Zn2Al[NO3 ] the area per unit charge is only 16.6 Å2” when it actually should be 25.0 Å2 confirmed by both our calculations and experiments.
22. Based on crystallographic data in the literature: (a) Brown, G.M., Noe-Spirlet, M.-R., Busing, W.R., Levy, H.A., Acta Cryst. B33, 1038 (1977). (b) H. D'Amour and R. Allmann, Z. Krist 143, 1 (1977). (c) J. Fuchs, A. Thiele and R. Palm, Z. Naturforsch. 366 161 (1981).


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