Controlled nucleation and growth studies in metal oxide and alkoxide systems by dynamic laser-light-scattering methods

Technical Report · Wed Apr 01 00:00:00 EST 1987

DOI:https://doi.org/10.2172/6870470· OSTI ID:6870470

Byers, C. H.; Brunson, R. R.; Harris, M. T.; Williams, D. F.

A method for studying the dynamics of crystallization by using an in situ crystallizer in a dynamic laser-light-scattering system has been developed. Results for growing systems in the size range of 0.005 to 1 ..mu..m may be monitored nondestructively using this method. In a series of tests, homogeneous precipitation techniques provide reproducible, controlled nucleation and growth of oxides such as hematite and silica. The effects of driving force and homogeneous and heterogeneous seeding were compared with a theoretical treatment of crystal formation and growth. The hydrolysis of tetraethoxysilicate (TEOS) in ethanol, n-butanol, and tert-butyl alcohol was investigated as a function of initial water and ammonia contents. Ethanol concentration, particle size, and number concentration were studied as a function of time. Preliminary results indicate that in the presence of excess water the growth rate of silica particles has a first-order dependence on TEOS concentration.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6870470
• Report Number(s): ORNL/TM-10285; ON: DE87009103
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTALLIZATION
MONITORING
OXIDES
CRYSTAL GROWTH
SILICA
SILICATES
HYDROLYSIS
LASER RADIATION
LIGHT SCATTERING
PARTICLE SIZE
PRECIPITATION
CHALCOGENIDES
CHEMICAL REACTIONS
DECOMPOSITION
ELECTROMAGNETIC RADIATION
LYSIS
MINERALS
OXIDE MINERALS
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
RADIATIONS
SCATTERING
SEPARATION PROCESSES
SILICON COMPOUNDS
SILICON OXIDES
SIZE
SOLVOLYSIS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication