Short-Range Dissolution-Precipitation Crystallization of Hydrothermal Barium Titanate

Journal Article · Thu Jul 01 04:00:00 EDT 2004 · Journal of the European Ceramic Society

DOI:https://doi.org/10.1016/j.jeurceramsoc.2003.12.007· OSTI ID:15020855

Qi, Lai; Lee, Burtrand I; Badheka, Prerak; Yoon, Dang-Hyok; Samuels, William D; Exarhos, Gregory J

A modified autoclave was used to investigate the crystallization mechanism of BaTiO3 during the hydrothermal reaction of Ba(OH)2 and TiO2 anatase. An uneven distribution of the crystallized BaTiO3 particles was observed: more than 99 wt% of total BaTiO3 articles remained where the precursor TiO2 was put; less than 1 wt% was collected from the areas away from the TiO2. According to the experimental observations in this work and proofs reported in the literature, we propose that the crystallization mechanism is dissolution-precipitation in nature, but the soluble Ti4+ species can only redisperse in a short distance away from TiO2 particles before precipitation. In another words, the nucleation of hydrothermal BaTiO3 starts at a low concentration of Ti4+. The mechanism of the Ba(OH)2-Ti(OH)4 reaction is a fast dehydration process.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 15020855
• Report Number(s): PNNL-SA-40411; KC0201050
• Journal Information: Journal of the European Ceramic Society, Journal Name: Journal of the European Ceramic Society Journal Issue: 13 Vol. 24
• Country of Publication: United States
• Language: English

Related Subjects

(D) BaTiO3 and titanates
(D) Perovskites
36 MATERIALS SCIENCE
BARIUM COMPOUNDS
CRYSTALLIZATION
DISSOLUTION
HYDROTHERMAL SYNTHESIS
Hydrothermal
NUCLEATION
PRECIPITATION
TITANATES