Journal of Materials Science

, Volume 29, Issue 7, pp 1807–1817 | Cite as

Effect of solvents and catalysts on monolithicity and physical properties of silica aerogels

  • A. Venkateswara Rao
  • G. M. Pajonk
  • N. N. Parvathy


The effect of various solvents and catalysts on the monolithicity and physical properties of silica aerogels is reported. The aerogels were prepared by hydrolysis and polycondensation of tetramethoxysilane, followed by hypercritical drying, using 6 solvents of different chain lengths, and 17 catalysts consisting of strong and weak acids, bases and their mixtures. It was found that solvents of longer chain lengths and strong basic catalysts resulted in semitransparent to opaque aerogels, whereas strong acids and their combinations with a weak basic catalyst produced transparent but cracked aerogels. While weak acids and their combinations with a weak base were found to produce shrunk and semitransparent (opaque for CH3COOH + NH4OH) aerogels, the best quality transparent, monolithic, low-density and refractive index, and large surface area aerogels were obtained for a combination of weak basic catalysts and solvents of shorter branching and chain lengths. The physical properties of the aerogels were studied by BET analysis, porosity, density, refractive index and optical transmission measurements.


Refractive Index Chain Length Large Surface Area NH4OH Polycondensation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    H. D. Gesser and P. C. Goswami, Chem. Rev, 89 (1989) 765.CrossRefGoogle Scholar
  2. 2.
    J. Fricke, Sci. Am. (1988) 92.Google Scholar
  3. 3.
    J. Fricke and G. Reidienauer, J. Non-Cryst. Solids 95, 96 (1987) 1135.CrossRefGoogle Scholar
  4. 4.
    U. Heinemann, E. Hummer, D. Biittner, R. Caps and J. Fricke, High Temp. High Press. 18 (1986) 517.Google Scholar
  5. 5.
    D. Buttner and J. Fricke, Int. J. Solar Energy 3 (1985) 89.CrossRefGoogle Scholar
  6. 6.
    A. Beck, R. Caps and J. Fricke, J. Phys. D Appl. Phys. 22 (1989) 730.CrossRefGoogle Scholar
  7. 7.
    R. Caps and J. Fricke, Solar Energy 36 (1986) 361.CrossRefGoogle Scholar
  8. 8.
    P. Scheuerpflug, R. Caps, D. Buttner and J. Fricke, Int. J. Heat Mass Transfer 28 (1985) 2299.CrossRefGoogle Scholar
  9. 9.
    J. Fricke and A. Emmerling, Struct. Bond. 77 (1992) 37.CrossRefGoogle Scholar
  10. 10.
    D. Buttner, R. Caps and J. Fricke, High Temp. High Press. 17 (1985) 375.Google Scholar
  11. 11.
    R. L. Guyer and D. E. Koshland Jr., Science 250 (1990) 1642.Google Scholar
  12. 12.
    S. S. Kistler and A. G. Caldwell, Ind. Eng. Chem. 26 (1934) 658.CrossRefGoogle Scholar
  13. 13.
    S. S. Kistler, J. Phys. Chem. 42 (1942) 19.CrossRefGoogle Scholar
  14. 14.
    J. F. White, Ind. Eng. Chem. 31 (1939) 827.CrossRefGoogle Scholar
  15. 15.
    M. Cantin, M. Casse, L. Koch, R. Jouan, P. Mestreau, D. Roussel, F. Bonnin, J. Moutel and S. J. Teichner, Nucl. Instrum. Meth. 118 (1974) 177.CrossRefGoogle Scholar
  16. 16.
    M. Bourdinaud, J. B. Cheze and J. C. Thevenin, ibid. 136 (1976) 99.CrossRefGoogle Scholar
  17. 17.
    P. J. Carlson, K. E. Johansson, J. Kesteman, J. Norsby, O. Pingot, S. Tavernier, F. Van den Bogaert and L. van Lancker, ibid. 160 (1979) 407.CrossRefGoogle Scholar
  18. 18.
    H. Burkhardt, P. Koehler, R. Riethmuller, B. H. Wük, R. Fohrmann, J. Franzke, H. L. Krosemann, R. Maschuur, G. Poelz, J. Reichardt, J. Ringel, O. Romer, R. Rusch, F. Schmuser, R. van Staa, J. Freeman, P. Leconte, T. Meyer, S. L. Wu and G. Zokernig, ibid. 184 (1981) 319.CrossRefGoogle Scholar
  19. 19.
    N. K. Kim, K. Kim, D. A. Payne and R. S. Upadhye, J. Vac. Sci. Technol. A7 (1989) 181.Google Scholar
  20. 20.
    K. Y. Jang, K. Kim and R. S. Upadhye, ibid. A8 (1990) 1732.CrossRefGoogle Scholar
  21. 21.
    K. Kim, K. Y. Jang and R. S. Upadhye, J. Am. Ceram. Soc. 74 (1991) 1987.CrossRefGoogle Scholar
  22. 22.
    S. J. Teichner, G. A. Nicolaon, M. A. Vicarini and G. E. E. Gar Des, Adv. Coll. Interf. Sci. 5 (1976) 245.CrossRefGoogle Scholar
  23. 23.
    D. Maret, G. M. Pajonk and S. J. Teichner, in “Catalysis on the Energy Scene”, edited by S. Kaliaguine and A. Mahay (Elsevier Science, Amsterdam 1984) p. 347.CrossRefGoogle Scholar
  24. 24.
    G. M. Pajonk, Appl. Catal. 72 (1991) 217.CrossRefGoogle Scholar
  25. 25.
    J. Fricke, M. C. Arduini-Schuster, D. Büttner, H. P. Ebert, U. Heinemann, J. Hetfleisch, E. Hummer, J. Kuhn and X. Lu, in “21st International Thermal Conductivity Conference”, 15–18 October 1989, Lexington, Kentucky.Google Scholar
  26. 26.
    A. J. Hunt, Lawrence Berkeley Laboratory, University of California, “LBL Research Review”, Summer 1991, p. 3.Google Scholar
  27. 27.
    C. S. Ashley, S. T. Read, C. J. Brinker, R. J. Walko, R. E. Ellefson and J. T. Gill, in “Sol-Gel Optics”, edited by J. D. Mackenzie and D. R. Ubrich, proc. SPIE 1328 (1990) 220. (SPIE, Washington, 1990.)Google Scholar
  28. 28.
    S. S. Kistler, Nature 127 (1931) 741.CrossRefGoogle Scholar
  29. 29.
    Idem, J. Phys. Chem. 36 (1932) 52.CrossRefGoogle Scholar
  30. 30.
    G. A. Nicolaon and S. J. Teichner, Bull. Soc. Chim. Fr. 5 (1968) 1900.Google Scholar
  31. 31.
    J. Zarzycki, M. Prassas and J. Phalippou, J. Mater. Sci. 17 (1982) 3371.CrossRefGoogle Scholar
  32. 32.
    J. Fricke (ed.), “Aerogels” (Springer, Berlin, 1986).Google Scholar
  33. 33.
    T. M. Tillotron and L. W. Hrubesh, Mater. Res. Soc. Symp. Proc. 180 (1990) 309.CrossRefGoogle Scholar
  34. 34.
    A. Venkateswara Rao and N. N. Parvathy, J. Mater. Sci. 28 (1993) 3021.CrossRefGoogle Scholar
  35. 35.
    S. Henning and L. Svensson, Phys. Scripta 23 (1981) 699.Google Scholar
  36. 36.
    G. Poelz and R. Riethmuller, Nucl. Instrum. Meth. 195 (1982) 491.CrossRefGoogle Scholar
  37. 37.
    M. Prassas, J. Phalippou and J. Zarzycki, J. Mater. Sci. 19 (1984) 1656.CrossRefGoogle Scholar
  38. 38.
    J. G. Van Lierop, A. Huizing, W. C. P. M. Meerman and C. A. M. Mulder, J. Non-Cryst. Solids 82 (1986) 265.CrossRefGoogle Scholar
  39. 39.
    R. A. Laudise and D. W. Johnson Jr, ibid. 79 (1986) 155.CrossRefGoogle Scholar
  40. 40.
    C. J. Brinker and G. W. Scherer, “Sol-Gel Science” (Academic Press, Boston, 1990).Google Scholar
  41. 41.
    L. L. Hench and J. K. West, Chem. Rev. 90 (1990) 33.CrossRefGoogle Scholar
  42. 42.
    S. G. Gregg and K. S. W. Sing, “Adsorption, Surface Area and Porosity” (Academic Press, London, 1982).Google Scholar
  43. 43.
    S. Brunauer, P. H. Emmert and E. Teller, J. Am. Chem. Soc. 62 (1940) 1723.CrossRefGoogle Scholar
  44. 44.
    W. G. Klemperer and S. D. Ramamurthi, Mater. Res. Soc. Symp. Proc. 121 (1988) 5.Google Scholar
  45. 45.
    V. Belot, R. Corriu, C. Guerin, B. Henner, D. Leclercq, H. Mutin, A. Vioux and Q. Wang, ibid. 180 (1990) 3.CrossRefGoogle Scholar
  46. 46.
    G. Hoang, J. Watson and T. W. Zerda, ibid 180 (1990) 15.CrossRefGoogle Scholar
  47. 47.
    M. G. Voronkov, V. P. Mileshkevich and Y. A. Yuzhelevski, “The Siloxane Bond” (Consultants Bureau, New York, 1978).Google Scholar
  48. 48.
    M. G. Voronkov and S. V. Barenko, Sov. Sci. Rev. B. Chem. 15 (1990) 1.Google Scholar
  49. 49.
    J. S. Kirk, US Pat. 2408 654-2408 656, Du Pont (1946).Google Scholar
  50. 50.
    R. K. Iler, J. Phys. Chem. 56 (1952) 673.CrossRefGoogle Scholar
  51. 51.
    C. J. Brinker, W. D. Drotning and G. W. Scherer, Mater. Res. Soc. Symp. Proc. 32 (1984) 25.CrossRefGoogle Scholar
  52. 52.
    R. K. Iler, “The Chemistry of Silica”, (Wiley, New York, 1979).Google Scholar
  53. 53.
    T. L. Brown and H. E. Le May Jr, “Chemistry: The Central Science”, 4th Edn (Prentice-Hall International, New York, 1990).Google Scholar
  54. 54.
    D. W. Schaefer and K. D. Keefer, Phys. Rev. Lett. 53 (1984) 1383.CrossRefGoogle Scholar
  55. 55.
    L. W. Kelts, N. J. Effinger and S. M. Melpolder, J. Non-Cryst. Solids 83 (1986) 353.CrossRefGoogle Scholar
  56. 56.
    D. W. Schaefer, C. J. Brinker, J. P. Wilcoxon, D. O. Wu, J. C. Phillips and B. Chu, Mater. Res. Soc. Symp. Proc. 121 (1988) 691.CrossRefGoogle Scholar

Copyright information

© Chapman & Hall 1994

Authors and Affiliations

  • A. Venkateswara Rao
    • 1
  • G. M. Pajonk
    • 1
  • N. N. Parvathy
    • 1
  1. 1.Laboratoire des Matériaux et Procédés CatalytiquesUniversité Claude Bernard Lyon IVilleurbanne CedexFrance

Personalised recommendations