Nanostructured Ceramics of Potassium Sodium Bismuth Titanate: Hydrothermal Synthesis and Piezoelectric Response at Morphotropic Phase Boundary
Open Access
- 1 January 2019
- journal article
- research article
- Published by Scientific Research Publishing, Inc. in New Journal of Glass and Ceramics
- Vol. 09 (01), 1-14
- https://doi.org/10.4236/njgc.2019.91001
Abstract
Potassium Sodium Bismuth Titanate (KNBT) ceramics, with the general formula (1 - x)K0.5Bi0.5TiO3 -xNa0.5Bi0.5TiO3, have been synthesized following hydrothermal route, starting with solid solutions of pure perovskite nanoceramics of KBT and NBT in desired stoichiometric weight ratios, followed by sintering between 850°C and 1000°C for few hours. Pure KNBT nanoceramics with perovskite structure, having mean particle size around 30 nm, could be obtained. Morphology of the samples is found to depend strongly on composition. A change of composition results in a phase change, as evident from X-ray structure analysis. This phase change is a result of rhombohedral to tetragonal morphotropic phase boundary (MPB) in the sample with x around 0.80. Composition dependent occurrence of MPB leads to formation of needle like structures with micrometer length scales. These are typical of tetragonal lamellar structures, suggesting partial induction of tetragonal polar order from rhombohedral structure at MPB. Dielectric and piezoelectric properties, such as dielectric constant and loss, piezoelectric coefficients and figures of merit, exhibit threshold maxima in their values at the composition corresponding to MPB. These values reported for a lead-free piezoceramic, synthesized by a comparatively simple hydrothermal route, are highly promising, and comparable to well-known PZT.Keywords
This publication has 23 references indexed in Scilit:
- Size-Controlled Hydrothermal Synthesis of Bismuth Sodium and Bismuth Potassium Titanates Fine Particles and Application to Lead-Free Piezoelectric CeramicsMATERIALS TRANSACTIONS, 2011
- Perspective on the Development of Lead‐free PiezoceramicsJournal of the American Ceramic Society, 2009
- The effect of (Li,Ce) doping in aurivillius phase material Na0.25K0.25Bi4.5Ti4O15Scripta Materialia, 2008
- Synthesis of Bismuth Sodium Titanate Fine Particles with Different Shapes by the Gel-Sol MethodMATERIALS TRANSACTIONS, 2007
- Fatigue In Bulk Lead Zirconate Titanate Actuator MaterialsAdvanced Engineering Materials, 2005
- A Lead‐Free High‐Curie‐Point Ferroelectric Ceramic, CaBi2Nb2O9Advanced Materials, 2005
- Layered Perovskites with Giant Spontaneous Polarizations for Nonvolatile MemoriesPhysical Review Letters, 2002
- Lanthanum-substituted bismuth titanate for use in non-volatile memoriesNature, 1999
- Dielectric and Piezoelectric Properties of (Bi0.5Na0.5)TiO3–(Bi0.5K0.5)TiO3 SystemsJapanese Journal of Applied Physics, 1999
- Templated Grain Growth of Textured Bismuth TitanateJournal of the American Ceramic Society, 1999