Electrochemical properties of Bi_{ass="a-plus-plus">4}Ti_{ass="a-plus-plus">3 – m class="a-plus-plus">xm>} Cr_{ass="a-plus-plus"> m class="a-plus-plus">xm>} O_{ass="a-plus-plus">12 – 0.5m class="a-plus-plus">xm>} (0.4 ≤ m class="a-plus-plus">xm> ≤ 1.2) solid solutions with a layered pero

详细信息    查看全文

• 作者：N. A. Sekushin ; M. S. Koroleva ; I. V. Piir
• 关键词：complex bismuth titanates ; layered perovskite structure ; impedance spectroscopy ; electron ; ion conductivity ; phase transition
• 刊名：Russian Journal of Electrochemistry
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：52
• 期：11
• 页码：1032-1040
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Electrochemistry; Physical Chemistry;
• 出版者：Pleiades Publishing
• ISSN：1608-3342
• 卷排序：52

文摘

Chromium-containing bismuth titanates Bi₄Ti_{3–m class="EmphasisTypeItalic ">x}Cr_xO_12–δ (0 ≤ x ≤ 1.2) with a layered perovskite structure and with the number of layers in the perovskite-like unit m = 3 at x ≤ 0.5 and m = 4 at 0.5 < x ≤ 1.2 were synthesized by the solid state method. The electrochemical properties of Bi₄Ti_1.8Cr_1.2O_11.38 (m = 4) and Bi₄Ti_2.6Cr_0.4O_11.8 (m = 3) were studied by impedance spectroscopy and DC electric conductivity measurements in different gas media. The oxygen conductivity increased at temperatures (t) of 450–500°C. For the samples with m = 4 at t ≥ 500°C in the frequency range of the order of a few Hz, the imaginary part of impedance was inverted, which was explained by the electrochemical process on electrodes. At t ≥ 600°C a reversible breakdown of the Bi₄Ti_2.6Cr_0.4O_11.8 sample in an electric field of over 30 V/m was observed. It was concluded that the conductivity of Bi₄Ti_{3–m class="EmphasisTypeItalic ">x}Cr_xO_12–δ is of electron-ion type.