Silica Sol as a Nanoglue: Flexible Synthesis of Composite Aerogels
10.1126/science.284.5414.622
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

Low-density nanoscale mesoporous composites may be readily synthesized by adding a colloidal or dispersed solid to an about-to-gel silica sol. The silica sol can “glue” a range of chemically and physically diverse particles into the three-dimensional silica network formed upon gelation. If the composite gel is supercritically dried so as to maintain the high porosity of the wet gel, a composite aerogel is formed in which the nanoscopic surface and bulk properties of each component are retained in the solid composite. The volume fraction of the second solid can be varied above or below a percolation threshold to tune the transport properties of the composite aerogel and thereby design nanoscale materials for chemical, electronic, and optical applications.

Bibliography

Morris, C. A., Anderson, M. L., Stroud, R. M., Merzbacher, C. I., & Rolison, D. R. (1999). Silica Sol as a Nanoglue: Flexible Synthesis of Composite Aerogels. Science, 284(5414), 622–624.

Authors 5
  1. Catherine A. Morris (first)
  2. Michele L. Anderson (additional)
  3. Rhonda M. Stroud (additional)
  4. Celia I. Merzbacher (additional)
  5. Debra R. Rolison (additional)
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  51. The ability to achieve conduction paths through carbon—(base-catalyzed) silica composite aerogels also demonstrates the importance of using an about-to-gel silica sol before introducing the particulate guest. We find that when the mixing or contact time between the silica oligomers and the carbon increases electronic paths cannot be established even for base-catalyzed silica.
  52. Supported by DARPA (Defense Advanced Research Projects Agency) and the Office of Naval Research (ONR). M.L.A. acknowledges a postdoctoral fellowship from ASEE (American Society for Engineering Education)–ONR. Helpful discussions with K. E. Swider Lyons and N. Leventis are gratefully acknowledged.
Dates
Type When
Created 23 years ago (July 27, 2002, 5:40 a.m.)
Deposited 8 months, 2 weeks ago (Dec. 8, 2024, 1:11 p.m.)
Indexed 6 days, 2 hours ago (Aug. 19, 2025, 6:11 a.m.)
Issued 26 years, 4 months ago (April 23, 1999)
Published 26 years, 4 months ago (April 23, 1999)
Published Print 26 years, 4 months ago (April 23, 1999)
Funders 0

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@article{Morris_1999, title={Silica Sol as a Nanoglue: Flexible Synthesis of Composite Aerogels}, volume={284}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.284.5414.622}, DOI={10.1126/science.284.5414.622}, number={5414}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Morris, Catherine A. and Anderson, Michele L. and Stroud, Rhonda M. and Merzbacher, Celia I. and Rolison, Debra R.}, year={1999}, month=apr, pages={622–624} }