Structural Peculiarities and Electrophysical Properties of Lithium Ion Conducting Lanthanum Niobate Prepared by Solid-State Reaction and Precipitation from Solution

✍ Scribed by Anatolii Belous; Oksana Gavrilenko; Olena Pashkova; Odile Bohnké; Claude Bohnké

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 261 KB
• Volume: 2008
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200701121

✦ Synopsis

Abstract

Synthesis of lithium ion conducting niobate was carried out by a conventional solid‐state reaction (SSR) and by precipitation from solution (PS). X‐ray powder diffraction was used to determine both intermediate phases that are formed during the preparation of these niobate from powder precursors and to determine the structure of sintered ceramics. It is shown that the PS technique leads to the formation of a perovskite phase at a lower temperature relative to the temperature required for the SSR technique. The electrophysical properties of the sintered ceramics were investigated by ac impedance spectroscopy. It is shown that not only the resistance but also the capacitance of the grain boundary are strongly affected by the method of synthesis used. It was found for the first time that the ceramic obtained from powders prepared by precipitation from solution can be used as pH sensors with good sensitivity (48 mV/pH) in the pH range from 4 to 10 and with a fast response time.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)