Synthesizing of Platelike {100} SrTiO<inf>3</inf> Particle by Topochemical Microcrystal Conversion Method

Abstract

Cubic perovskite-structured platelike SrTiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> particles were synthesized by topochemical microcrystal conversion (TMC) method from platelike precursor of layer-structured SrBi <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> Ti <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sub> particles. SrTiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> particles inherited the shape of precursor particles having a thickness of about 0.5 microns and a width of 5-10 microns. X-ray diffraction measurement of cast particles on glass substrate elucidated that in the TMC reaction, the crystallographic {001} plane of SrBi <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> Ti <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sub> is converted into the {100} plane of SrTiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> . With use of the platelike SrTiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> particles as a template by templated grain growth method, dense {100} grain-oriented SrTiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ceramics having a {100} orientation degree (Logerring's factor) larger than 91% were fabricated at sintering temperatures between 1350degC to 1550degC. The maximum orientation factor was 99.3%. The textured ceramics had a unique microstructure of well aligned brick wall-like grains in the side face to tape-cast plane observed by scanning electron microscopy.