Sol-gel and ultrafine particle formation via dielectric tuning of inorganic salt-alcohol-water solutions

Journal Article · Tue Feb 01 04:00:00 EST 2000 · Journal of Colloid and Interface Science

DOI:https://doi.org/10.1006/jcis.1999.6610· OSTI ID:20017490

Hu, M Z.C.; Payzant, E A; Byers, C H

In this work, the formation of monodispersed hydrous zirconia microsphere particles (particularly nanosized) and gels was achieved in solutions of zirconyl chloride dissolved in alcohol-water mixed solvents. A lower dielectric constant of mixed solvent corresponds to a lower solubility of inorganic solute and, thus, a shorter induction period for nucleation as well as higher solid particle growth kinetics. The sol-gel processes in the mixed solvent system can be adjusted using the processing parameters, including the initial inorganic salt concentration (C), alcohol/aqueous medium volume ratio of the mixed solution (RH), incubation temperature (T), incubation time (t), concentration of hydroxypropyl cellulose (HPC), and ammonia neutralization. Monodispersed submicron and nanoscale (<100 nm) zirconia microspheres/powders were successfully synthesized under conditions of high RH (5) and using HPC (molecular weight of 100,000, 2.0 x 10{sup {minus}3} g/cm{sup 3}) and ammonia neutralization. Initial salt concentration affects the particle size significantly. Gel materials were obtained under conditions of low RH (1.0). Microstructure and transparency of gels changed significantly from low (0.05 M) to high (0.2 M) concentration of the metal salt. The authors have also demonstrated that monodispersed particle production can be achieved not only at low temperatures (<100 C) but also at room temperature using an inorganic salt precursor.

• Research Organization: Oak Ridge National Lab., TN (US)
• Sponsoring Organization: US Department of Energy
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 20017490
• Journal Information: Journal of Colloid and Interface Science, Journal Name: Journal of Colloid and Interface Science Journal Issue: 1 Vol. 222; ISSN 0021-9797; ISSN JCISA5
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALCOHOLS
CERAMICS
GELS
MIXED SOLVENTS
PARTICLES
PRECURSOR
SOL-GEL PROCESS
WATER
ZIRCONIUM OXIDES