Journal of the American Ceramic Society, Vol.89, No.12, 3850-3853, 2006
Plate-like Na0.5Bi0.5TiO3 template synthesized by a topochemical method
Large plate-like Na0.5Bi0.5TiO3 (NBT) templates have been successfully synthesized from bismuth layer-structured ferroelectric Na0.5Bi4.5Ti4O15 (NBIT) particles by the topochemical method. Because of the highly anisotropic structure, plate-like NBIT particles were first synthesized by the molten-salt process. After the topochemical reaction with the complementary reactants (Na2CO3, and TiO2) in NaCl flux, the layer-structured NBIT particles were transformed to the perovskite NBT templates. The resulting NBT templates are large and of plate-like shape. Our results also reveal that they are more effective in inducing grain orientation in the BNKT-BT ceramics as compared with BIT templates. For a BNKT-BT ceramic textured with 20 wt% of NBT templates, it exhibits a very high degree of grain orientation and gives a large Lotgering factor of 0.89.