Preparation of nanocrystalline ferroelectric CaBi2Ta2O9 by the urea method

• Published in: Ceramics international Vol. 31; no. 6; pp. 773 - 775
• Main Authors: GAIKWAD, S. P, PASRICHA, Renu, RAVI, V
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Science 2005
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Chemistry; Colloidal state and disperse state; Cross-disciplinary physics: materials science; rheology; Electrotechnical and electronic ceramics; Exact sciences and technology; General and physical chemistry; Materials science; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Physics; Powders; Technical ceramics; Particle size; Calcium oxide; Ultrafine powder; Precursor; Oxide ceramics; Chemical preparation; Manufacturing; Growth from solution; Nanocrystal; Electroceramics; Bismuth Calcium Tantalum Oxides Mixed; Electrical properties; Chemical precipitation; Dielectric properties; Ferroelectric ceramics; Tantalum fluoride; Experimental study; Ferroelectric properties; X ray diffraction; Calcium chloride; Bismuth chlorides; Urea; Transmission electron microscopy; Morphology; Aqueous solution
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2004.08.011

A precipitate was formed when an aqueous solution of CaCl2, BiCl3, TaF5 and urea in stoichiometric ratio was heated on a water bath. This precipitate on decomposition at 600 C yielded nanocrystallites of ternary oxide CaBi2Ta2O9 (CBT) as confirmed by XRD. Particle size and morphology was studied by TEM. Ferroelectric hysteresis loop parameters such as remanent polarisation and coercive field were also determined. TEM investigations revealed that the average particle size of the polycrystalline powder was 70 nm. The room temperature dielectric constant was 110. 12 refs.