Defects and Transport Properties in TiNb2O7. Issue 12 (2nd September 2013)

• Record Type: Journal Article
• Authors: Xing, Wen; Kalland, Liv‐Elisif; Li, Zuoan; Haugsrud, Reidar; Stevenson, J.
• Is Part Of: Journal of the American Ceramic Society. Volume 96:Issue 12(2013)
• Page Start: 3775
• Page End: 3781
• Publication Date: 2013-09-02
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.12558
• Languages: English
• ISSNs: 0002-7820

Abstract

<abstract abstract-type="main" id="jace12558-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The electrical conductivity of TiNb<sub>2</sub>O<sub>7</sub> was characterized as a function of temperature, <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zmnbs8r" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="urn:x-wiley:00027820:media:jace12558:jace12558-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="bold-italic">p</mml:mi></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="bold">O</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:msub></mml:mrow></mml:math></alternatives> and <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zmnbs76" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="urn:x-wiley:00027820:media:jace12558:jace12558-math-0002" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi>H</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:mi mathvariant="normal">O</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math></alternatives>. The total conductivity was independent of <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zmnbrw5" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="urn:x-wiley:00027820:media:jace12558:jace12558-math-0003" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi>O</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:msub></mml:mrow></mml:math></alternatives> in the low oxygen partial pressure regime, while a dependency of <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zmnbrxq" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="urn:x-wiley:00027820:media:jace12558:jace12558-math-0004" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:msubsup><mml:mrow><mml:mi>O</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow><mml:mrow><mml:mo>−</mml:mo><mml:mn>1</mml:mn><mml:mo stretchy="false">/</mml:mo><mml:mn>4</mml:mn></mml:mrow></mml:msubsup></mml:mrow></mml:msub></mml:mrow></mml:math></alternatives> was observed at higher oxygen partial pressures. The conductivity increased with increasing <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg3zmnbrz8" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math altimg="urn:x-wiley:00027820:media:jace12558:jace12558-math-0005" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:msub><mml:mrow><mml:mi>H</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:mi mathvariant="normal">O</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math></alternatives> under oxidizing conditions below 700°C. Mixed electronic and protonic conduction was indicated by H/D isotope exchange and transport number measurements. A defect model based on interstitial type of hydration was established and fitted to the conductivity data allowing for determination of physicochemical parameters of hydration and electron migration.</p> </abstract>