Synthesis of Na0.5Bi0.5TiO3 Submicron Particles in Molten Salt
Powder size is a major factor determining the characteristics of processing variables and end-products of ceramic materials. Na0.5Bi0.5TiO3 is one of the potential candidates for non-lead piezoelectric materials, synthesis of Na0.5Bi0.5TiO3 particles in molten salt was studied. Two salt systems, NaCl-KCl and Na2SO4-3K2SO4 were investigated. Only at 850°C and above, BNT was completely formed without any secondary phases in both eutectic chloride and sulfate salt. By substituting chloride with sulfate, the particle size of BNT could be greatly reduced to a few hundreds nanometer at 850°C. Submicron particles of SrTiO3 could also be synthesized in eutectic sulfate salt at 850°C, It is evident that molten salt synthesis could be employed to produce submicron particles of Na0.5Bi0.5TiO3 and SrTiO3. Molten salt synthesis is low-cost and capable to produce fine powders of various complex-oxides.
P. Setasuwon and S. Kijamnajsuk, "Synthesis of Na0.5Bi0.5TiO3 Submicron Particles in Molten Salt", Advanced Materials Research, Vols. 55-57, pp. 161-164, 2008