Preparation of nanocrystalline ferroelectric BaNb₂O₆ by citrate gel method

A gel was formed when a aqueous solution of BaCl₂, NbF ₅ and citric acid in stoichiometric ratio is heated on a water bath. This gel on decomposition at 600°C yielded the nano crystallites of BaNb₂O₆, 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°C) as reported for the formation of BaNb ₂O₆. 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.