Premium
Preparation of Fine Tetragonal Barium Titanate Powder by a Microwave–Hydrothermal Process
Author(s) -
Sun Weian,
Li Junqing,
Liu Wen,
Li Chuiha
Publication year - 2006
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2005.00649.x
Subject(s) - tetragonal crystal system , stoichiometry , hydrothermal circulation , barium titanate , materials science , hydrothermal synthesis , lattice constant , alkali metal , particle size , enthalpy , barium , crystal structure , hydroxide , mineralogy , crystallography , analytical chemistry (journal) , inorganic chemistry , chemical engineering , ceramic , chemistry , diffraction , metallurgy , organic chemistry , physics , optics , engineering , quantum mechanics
A microwave–hydrothermal (MH) process was performed at 240°C to prepare tetragonal BaTiO 3 from TiCl 4 and Ba(OH) 2 . No alkali hydroxide was used to avoid contaminations. MH BaTiO 3 powder with a c / a ratio of 1.010 and a mean size of 180 nm was synthesized within only 9 h. The MH BaTiO 3 contains a very low concentration of lattice hydroxyl group, associated with a very small lattice strain. The measured density of the MH BaTiO 3 is favorably consistent with the theoretical value, and the Ba/Ti stoichiometry determined is 0.996. The formation of a tetragonal structure in BaTiO 3 and the particle growth were strongly promoted by the MH process. The effects of lattice defects on the stoichiometry and the determination of transition enthalpy were discussed.