Plate‐Like Na _0.5 Bi _0.5 TiO ₃ Template Synthesized by a Topochemical Method

Abstract

Large plate‐like Na 0.5 Bi 0.5 TiO 3 (NBT) templates have been successfully synthesized from bismuth layer‐structured ferroelectric Na 0.5 Bi 4.5 Ti 4 O 15 (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 (Na 2 CO 3 , and TiO 2 ) 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.