Porous silicon oxycarbide glasses

Anant K. Singh, Carlo G. Pantano

Research output: Contribution to journalArticlepeer-review

37 Scopus citations

Abstract

High-surface-area silicon oxycarbide gels and glasses were synthesized from mixtures of methyldimethoxysilane (MDMS) and tetraethoxysilane (TEOS) through acidic hydrolysis and condensation. A surface area of ∼275 m2/g and an average pore size of ∼30 Å was obtained for a 50% MDMS-50% TEOS glass at 800°C under a flowing argon atmosphere. The average pore size was increased by aging the precursor gels in ammonium hydroxide. The increased average pore size and the higher strength of the mesoporous gel network enhanced the surface-area stability of the glasses; in this case, surface areas >200 m2/g were retained at 1200°C under an argon atmosphere. 29Si MAS NMR spectra revealed that an oxycarbide structure was established in the mesoporous glasses obtained after pyrolysis of the aged gels. The role of carbon was demonstrated by comparing the surface-area stability of the oxycarbide glasses with that of pure silica and that of oxycarbide glasses where all the carbon groups were removed through low-temperature plasma-oxidation treatments. In the absence of carbon, the thermal stability of the surface area decreased dramatically.

Original languageEnglish (US)
Pages (from-to)2696-2704
Number of pages9
JournalJournal of the American Ceramic Society
Volume79
Issue number10
DOIs
StatePublished - Oct 1996

All Science Journal Classification (ASJC) codes

  • Ceramics and Composites
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Porous silicon oxycarbide glasses'. Together they form a unique fingerprint.

Cite this