Facile preparation of transparent monolithic titania gels utilizing a chelating ligand and mineral salts

Joji Hasegawa, Kazuyoshi Kanamori, Kazuki Nakanishi, Teiichi Hanada

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

Highly homogeneous transparent titania gels have been successfully prepared from titanium alkoxide by a sol-gel method utilizing chelating agent, ethyl acetylacetate (EtAcAc), in the presence of strong acid anions. Only catalytic amount of a strong acid anion suppress the rapid hydrolysis of titanium alkoxide by blocking the nucleophilic attack of HO- and H2O, and the resultant moderate sol-gel reactions thus afford homogeneous gelation, leading to transparent monolithic titania gels. Gelation time can be widely controlled by changing amounts of water, chelating agent and salt. The ability of salts to suppress the too abrupt sol-gel reactions is strongly dependent on the electronegativity of anions and valence of cations. With employing NH 4NO3 as a suppressing electrolyte, the obtained titania gels can be converted to pure TiO2 by simple washing and heat-treatment, and transformations to anatase and rutile structures were found to start at 400 and 600 °C, respectively.

Original languageEnglish
Pages (from-to)59-66
Number of pages8
JournalJournal of Sol-Gel Science and Technology
Volume53
Issue number1
DOIs
Publication statusPublished - Jan 1 2010

Fingerprint

Chelation
Minerals
Gels
titanium
Titanium
Salts
Ligands
minerals
gels
salts
preparation
ligands
Anions
Negative ions
Gelation
Chelating Agents
alkoxides
gelation
Sol-gels
anions

All Science Journal Classification (ASJC) codes

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

Cite this

Facile preparation of transparent monolithic titania gels utilizing a chelating ligand and mineral salts. / Hasegawa, Joji; Kanamori, Kazuyoshi; Nakanishi, Kazuki; Hanada, Teiichi.

In: Journal of Sol-Gel Science and Technology, Vol. 53, No. 1, 01.01.2010, p. 59-66.

Research output: Contribution to journalArticle

Hasegawa, Joji ; Kanamori, Kazuyoshi ; Nakanishi, Kazuki ; Hanada, Teiichi. / Facile preparation of transparent monolithic titania gels utilizing a chelating ligand and mineral salts. In: Journal of Sol-Gel Science and Technology. 2010 ; Vol. 53, No. 1. pp. 59-66.
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