Preparation and characterization of barium titanate sol with long time stability

Nanostructured film of barium titanate is known as a key material for different applications such as memories, thermistors, sensors, actuators and various electro-optic devices. Multilayer ceramic capacitors (MLCC), semiconductors with positive temperature coefficient of resistance (PTCR) and pyroelectric detectors are other possibilities applications of this material. Sol-gel is one of the methods that can be used for giving pure and doped barium titanate thin nanofilm in the low temperature procedure. In this method the addition of a dopant element can be done more exactly than conventional solid state methods. In this research a highly stable, water-based BaTiO3 sol system was developed by a chelate acetate sol-gel process. Acetate derived barium titanate sol was prepared by glacial acetic acid, barium acetate, titanium isopropoxide (TTIP), 2- propanol and water precursors. Barium acetate was dissolved in hot glacial acetic acid (molar ratio 1/6). After cooling, TTIP is added in stoichiometric amount (molar ratio Ba/Ti = 1). A two stage hydrolysis was performed by adding excess water (molar ratio H2O/Ti = 150) after introducing 2-propanol to solution. Sols that prepared by this procedure was stable excess than 6 months to ever. UV-Visible photospectrometer and Fourier transform infrared (FT-IR) analysis was used for characterization of the prepared sol.

کلیدواژه ها:

Nanostructured films ، Barium titanate ، Sol-gel technique ، high stability sol