Preparation of nanocrystalline ferroelectric BaNb_2O_6 by citrate gel method

摘要

A gel was formed when a aqueous solution of BaCl_2, NbF_5 and citric acid in stoichiometric ratio is heated on a water bath. This gel on decomposition at 600 deg C yielded the nano crystallites of BaNb_2O_6, as confirmed by X-ray diffraction study (XRD). This is a much lower temperature as compared to that prepared by traditional solid state method (1000 deg C) as reported for the formation of BaNb_2O_6. Transmission electron microscopic (TEM) Investigations revealed that the average particle size is 50 nm for the calcined powders. The room temperature dielectric constant at 1 kHz is found to be 1000. The ferroelectric hysteresis loop parameters of these samples were also studied.