Plate-Like Na0.5Bi0.5TiO3 Template Synthesized by a Topochemical Method.

Authors :: Zeng, J. T.
Kwok, K. W.
Tam, W. K.
Tian, H. Y.
Jiang, X. P.
Chan, H. L. W.
Source :: Journal of the American Ceramic Society; Dec2006, Vol. 89 Issue 12, p3850-3853, 4p, 2 Black and White Photographs, 3 Graphs
Publication Year :: 2006
Abstract: Large plate-like Na<subscript>0.5</subscript>Bi<subscript>0.5</subscript>TiO<subscript>3</subscript> (NBT) templates have been successfully synthesized from bismuth layer-structured ferroelectric Na<subscript>0.5</subscript>Bi<subscript>4.5</subscript>Ti<subscript>4</subscript>O<subscript>15</subscript> (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<subscript>2</subscript>CO<subscript>3</subscript>, and TiO<subscript>2</subscript>) 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. [ABSTRACT FROM AUTHOR]