Effects of aging and drying on structure of V2O5 gels

Hiroshi Hirashima, Manabu Gengyo, Chihiro Kojima, Hiroaki Imai

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Semiconducting V2O5 gels with and without addition of GeO2 were prepared by hydrolysis of metal alkoxides in alcoholic solutions. Wet gels, xerogels dried at room temperature and supercritically dried aerogels, were characterized by transmission electron microscopy, X-ray diffraction and small-angle X-ray scattering. Crystalline vanadium oxides were not observed in xerogels, but V3O7 diffraction peaks were found for the aerogels kept at 250°C and 210 atm for 2 h or longer before drying. In the Porod region, in the range of scattering vector between about 10−2 and 10−1 Å−1, the power law was valid for wet and dry gels. Wet gels and aerogels are mass fractals. The fractal dimension of the wet gels increased from 2.1 to 3 during aging, but scarcely changed with supercritical drying. Xerogels are surface fractals with a surface fractal dimension of 2.1–2.5.

Original languageEnglish
Pages (from-to)54-58
Number of pages5
JournalJournal of Non-Crystalline Solids
Volume186
DOIs
Publication statusPublished - 1995

Fingerprint

drying
Drying
Gels
Aging of materials
Xerogels
xerogels
gels
Aerogels
fractals
aerogels
Fractal dimension
Fractals
Vanadium
vanadium oxides
alkoxides
X ray scattering
scattering
diffraction
Oxides
hydrolysis

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Condensed Matter Physics
  • Materials Chemistry

Cite this

Effects of aging and drying on structure of V2O5 gels. / Hirashima, Hiroshi; Gengyo, Manabu; Kojima, Chihiro; Imai, Hiroaki.

In: Journal of Non-Crystalline Solids, Vol. 186, 1995, p. 54-58.

Research output: Contribution to journalArticle

Hirashima, Hiroshi ; Gengyo, Manabu ; Kojima, Chihiro ; Imai, Hiroaki. / Effects of aging and drying on structure of V2O5 gels. In: Journal of Non-Crystalline Solids. 1995 ; Vol. 186. pp. 54-58.
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