Mobility size development and the crystallization path during aerosol decomposition synthesis of TiO2 particles

Citation
Pp. Ahonen et al., Mobility size development and the crystallization path during aerosol decomposition synthesis of TiO2 particles, J AEROS SCI, 32(5), 2001, pp. 615-630
Citations number
30
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemical Engineering
Journal title
JOURNAL OF AEROSOL SCIENCE
ISSN journal
0021-8502 → ACNP
Volume
32
Issue
5
Year of publication
2001
Pages
615 - 630
Database
ISI
SICI code
0021-8502(200105)32:5<615:MSDATC>2.0.ZU;2-O
Abstract
Size and morphology transformation as well as the crystallization path of m onodisperse titanium dioxide particles were studied in aerosol flow reactor . Solid, hydrated titanium oxide particles were prepared from titanium alko xide by a droplet hydrolysis acid a subsequent size classification. The par ticles were carried to a reactor in air at temperature range of 20-1500 deg reesC. The inlet particle size of 100 and 200 nm gradually decreased 40% wi th increasing temperature as investigated by a tandem differential mobility analyzer (TDMA) system. The decrease was due to decomposition of the hydra ted Ti-O particles. densification of the forming TiO2 particles, and a phas e change from anatase to rutile. Above 1000 degreesC the mobility size incr eased due to crystal-habit formation that created faceted, elongated partic les and consequently an increased dynamic shape factor. Microstructure inve stigations with a transmission electron microscope (TEM) showed that nanocr ystalline anatase particles were present at 600 degreesC and transformed to rutile up to 1100 degreesC with simultaneous crystallite growth. Single-cr ystal rutile particles were observed at temperatures with the increased mob ility diameters. (C) 2001 Elsevier Science Ltd. All rights reserved.