Porous silicon oxycarbide glasses from organically modified silica gels of high surface area

Chunling Liu, Hanxi Zhang, Sridhar Komarneni, Carlo G. Pantano

Research output: Contribution to journalArticle

32 Scopus citations

Abstract

High surface area alkyl-substituted silica aerogels and xerogels were successfully prepared by sol-gel processing and supercritical drying. The gels were further heat treated in inert atmosphere to temperatures as high as 1000°C. Surface areas and pore structure of the gels and gels pyrolyzed at high temperatures were determined by multipoint BET surface area measurement. The aerogels and xerogels exhibited surface areas of about 1100 m2/g. No significant effect of pH was found on the surface areas of gels in the two step sol-gel process, but gels of low pH showed smaller pore diameter and higher density. Xerogels showed smaller surface area, pore size, and pore volume compared to aerogels. Upon pyrolyzing in inert atmosphere, the surface areas of all the gels decreased with temperature as a result of collapse of micropores and shrinkage of mesopores. Unlike pure silica gel, which loses almost all surface area and densifies at 1000°C, the advantage of the alkyl-substituted gels is that they maintained a high surface area of 400 m2/g at 1000°C.

Original languageEnglish (US)
Pages (from-to)141-151
Number of pages11
JournalJournal of Sol-Gel Science and Technology
Volume1
Issue number2
DOIs
StatePublished - Jan 1 1994

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Chemistry(all)
  • Biomaterials
  • Condensed Matter Physics
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Porous silicon oxycarbide glasses from organically modified silica gels of high surface area'. Together they form a unique fingerprint.

  • Cite this