Effect of pH on the final connectivity distribution of the silicon atoms in the Stöber particles

Kangtaek Lee, Alon McCormick

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Using 29Si MAS-NMR we investigate the effect of pH on the final connectivity distribution of the silicon atoms in the Stöber particles. Our data suggest that the fraction of the silicon atoms that are ully-connected decreases as the ammonia concentration is increased. This suggests a more negative first shell substitution effect in the precipitated phase (liquid droplet) if condensation reactions are irreversible. A simple model is developed to describe the condensation kinetics in the precipitated phase and the results support the negative first shell substitution effect. These findings challenge the notion of a positive first shell substitution effect in alkaline conditions.

Original languageEnglish
Pages (from-to)255-260
Number of pages6
JournalJournal of Sol-Gel Science and Technology
Volume33
Issue number3
DOIs
Publication statusPublished - 2005 Mar 1

Fingerprint

Silicon
Substitution reactions
Atoms
silicon
substitutes
atoms
Condensation reactions
condensation
Ammonia
Condensation
Nuclear magnetic resonance
ammonia
liquid phases
Kinetics
Liquids
nuclear magnetic resonance
kinetics

All Science Journal Classification (ASJC) codes

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

Cite this

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Effect of pH on the final connectivity distribution of the silicon atoms in the Stöber particles. / Lee, Kangtaek; McCormick, Alon.

In: Journal of Sol-Gel Science and Technology, Vol. 33, No. 3, 01.03.2005, p. 255-260.

Research output: Contribution to journalArticle

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