Organogels are useful as a template for the preparation of novel helical silica fibers

Yoshiyuki Ono, Kazuaki Nakashima, Masahito Sano, Junichi Hojo, Seiji Shinkai, Seiji Shinkai, Seiji Shinkai

Research output: Contribution to journalArticle

85 Citations (Scopus)

Abstract

Sol-gel polymerization of tetraethoxysilane (TEOS) was carried out in the organogel phase consisting of cholesterol-based gelators (neutral 1 and cationic 2). TEOS polymerization in neutral 1 + MeCO2H gel resulted in the conventional granular silica whereas that in cationic 2 + MeCO2H gel yielded the novel mesoporous silica with a tubular structure. SEM and TEM observations and additive effects established that the organogel fibers act as a template in the TEOS polymerization process to yield the hollow silica fibers and that the electrostatic interaction plays a crucial role in adsorption of anionic oligomeric silica particles onto the cationic organogel fiber surface. Thus, the tubular structure is created after combustion of the gelators by calcination. Very interestingly, when TEOS polymerization was carried out in the 1 + 2 mixed organogel, fibrous silica with a right-handed "helical" structure was created. This phenomenon appeared only in the range of 2/(1 + 2) = 5-15 mol%. Since the higher-order helical structure is characteristic of supramolecular assemblies of "chiral" organic compounds, it is suggested that the chirality in the organogel fibers is successfully transcribed into the inorganic silica fibers. Thus, the concept presented in this paper describes a novel template effect and should be broadly applicable to the design of "supramolecular" silica materials useful for catalysts, memory storage, replication, etc.

Original languageEnglish
Pages (from-to)2412-2419
Number of pages8
JournalJournal of Materials Chemistry
Volume11
Issue number10
DOIs
Publication statusPublished - Jan 1 2001
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Organogels are useful as a template for the preparation of novel helical silica fibers'. Together they form a unique fingerprint.

  • Cite this

    Ono, Y., Nakashima, K., Sano, M., Hojo, J., Shinkai, S., Shinkai, S., & Shinkai, S. (2001). Organogels are useful as a template for the preparation of novel helical silica fibers. Journal of Materials Chemistry, 11(10), 2412-2419. https://doi.org/10.1039/b102550n