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Micro-Raman Spectroscopy of Fresh and Aged Silica Gels†

Published online by Cambridge University Press:  15 February 2011

L. C. Klein ,
C. Nelson  and
K. L. Higgins
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Abstract

Raman spectra were obtained from fresh and aged silica gels using micro-Raman techniques. Comparison of the spectra from wet and dried gels reveals the stages of reaction in the ethanol-TEOS-water system and the gradual development of the silica structure. The steady disappearance of bands assigned to ethanol and the appearance of bands assigned to silatious species can be traced during the drying process. Increases in either acid concentration or water level increase reaction rates to give gels in a more advanced stage of polymerization. Gels tend to develop fluorescence upon aging for several months. The source of this fluorescent could not be determined, but it's development can be prevented by heating freshly dried gels to about 155°C.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 32: Symposium B – Better Ceramics Through Chemistry I , 1984 , 293
Copyright
Copyright © Materials Research Society 1984

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Footnotes

†

This work performed at Sandia National Laboratories supported by the U. S. Department of Energy under Contract Number DE-AC04-76DP00789.

References

REFERENCES

1. Bertoluzza, A. et al. . Raman and infrared spectra on silica gel evolving toward glass. J. Non-Crystal. Solids 48 (1982) 117–128.CrossRefGoogle Scholar
2. Krol, D. M. and vanLierop, J. G.. The densification of monolithic gels. J. Non-Crystal. Solids (1983) to be published.Google Scholar
3. Gottardi, V., Guglielmi, M. et al. . Further investigations on Raman spectra of silica gel evolving toward glass. J. Non-Crystal. Solids (1983) to be published.Google Scholar
4. Krol, D. M. and vanLierop, J. G.. Raman study of the water adsorption on monolithic silica gels. Submitted to J. Non-Crystal. Solids (1983).Google Scholar
5. Revesz, A. G. and Walrafen, G. E.. Structural interpretations for some Raman lines from vitreous silica. J. Non-Crystal. Solids 54 (1983) 323–333.Google Scholar
6. Nogami, M. and Moriya, Y.. Glass formation through hydrolysis of Si(OC2 H5)4 with NH4OH and HCl solution. J. Non-Crystal. Solids 37 (1980) 191–201.CrossRefGoogle Scholar
7. Kamiya, K., Sakka, S. and Mizutani, M.. Preparation of silica glass fibers and transparent silica glass from silicon tetraethoxide. Yogyo-Kyokai-Shi 86 (1978) 553–559.Google Scholar
8. Decottingnies, M., Phalippou, J. and Zarzycki, J.. Synthesis of glasses by hot-pressing of gels. J. Mat. Sci. 13 (1978) 2605–2618.Google Scholar
9. Gallo, T. A. et al. . The role of water in densificaton of gels. This volume (1984).Google Scholar
10. Klein, L. C., Gallo, T. A. and Garvey, G. J.. Densification of monolithic silica gels below 1000°C. J. Non-Crystal. Solids (1983) to be published.CrossRefGoogle Scholar
11. Brinker, C. J. et al. . Sol-gel transition in simple silicates. J. Non-Crystal. Solids 48 (1982) 47–64.CrossRefGoogle Scholar
12. Brinker, C. J. et al. . Sol-gel transition in simple silicates II. J. Non-Crystal. Solids (1983) to be published.Google Scholar
13. Tallant, D. R., Higgins, K. L. and Stein, C. L.. Raman spectroscopy through transparent materials, in Microbeam Analysis-1983, ed. Gooley, R., San Francisco, pp. 297–300.Google Scholar
14. Klein, L. C. and Garvey, G. J.. Effect of water on acid- and basecatalyzed hydrolysis and tetraethyl orthosilicate (TEOS) This volume (1984).Google Scholar
15. Brawer, S. A. and White, William B.. Raman Spectroscopic Investigation of the Structure of Silicate Glasses. J. Chem. Physics. Vol. 63 No. 6, Sept. 15, 1975.CrossRefGoogle Scholar
16. Wolf, A. A. et al. Radiation-induced defects in glasses with high water content. J. Non-Crystal. Solids 56 (1983) 349–354.CrossRefGoogle Scholar