Scholarlink

<p>Building upon the Na<sub>0.5</sub>Bi<sub>0.49-x</sub>Ca<sub>x</sub>Ti<sub>0.99</sub>Mg<sub>0.01</sub>O<sub>3-δ</sub> system previously reported for its optimal electrical performance, we synthesized a series of calcium-doped ceramics with compositions Na<sub>0.5</sub>Bi<sub>0.49-x</sub>Ca<sub>x</sub>- Ti<sub>0.99</sub>Mg<sub>0.01</sub>O<sub>3-δ</sub> (x = 0, 0.01, 0.02, 0.03) using the solid-phase method. The ceramics underwent precisely controlled two-step thermal processing: initial calcination at 800&#xa0;°C followed by sintering at 1000 °C, with rigorous stoichiometric control maintained across all samples. The samples were characterized by XRD, SEM, and AC impedance spectroscopy to study the effect of Ca<sup>2+</sup> doping concentration on the crystal structure, morphology and electrical properties of samples, specially, the bulk conductivity (<InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10008_2025_6449_Article_IEq1.gif" Format="GIF" Height="12" Rendition="HTML" Resolution="72" Type="Linedraw" Width="18" /> </InlineMediaObject> <EquationSource Format="TEX">\(\sigma_b\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>σ</mi> <mi>b</mi> </msub> </math></EquationSource> </InlineEquation>), grain boundaries conductivity (<InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10008_2025_6449_Article_IEq2.gif" Format="GIF" Height="17" Rendition="HTML" Resolution="72" Type="Linedraw" Width="31" /> </InlineMediaObject> <EquationSource Format="TEX">\(\sigma gb\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mi>σ</mi> <mi>g</mi> <mi>b</mi> </mrow> </math></EquationSource> </InlineEquation>), and total conductivity (<InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10008_2025_6449_Article_IEq3.gif" Format="GIF" Height="12" Rendition="HTML" Resolution="72" Type="Linedraw" Width="17" /> </InlineMediaObject> <EquationSource Format="TEX">\(\sigma_{t}\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>σ</mi> <mi>t</mi> </msub> </math></EquationSource> </InlineEquation>), which obtained by the fitted impedance spectra, were analyzed in detail to reveal the effect of Ca<sup>2+</sup>-doping on the electrical performance. The findings revealed that all the samples displayed a pure perovskite phase without discernible impurity peaks. Furthermore, the average grain size of the samples decreased as the doping concentration was increased, suggesting that Ca<sup>2+</sup> play a role in retarding grain growth. Upon substitution of Bi<sup>3+</sup> with Ca<sup>2+</sup>, the grain conductivity peaked at a doping ratio of x = 0.02. The grain boundary conductivity, on the other hand, increased initially with the rise in x before declining, reaching its maximum at x = 0.01. Consequently, the total conductivity was found to be at its highest when x = 0.01.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Effect of Ca2+ doping on the structure and electrical properties of Na0.5Bi0.49-x Cax Ti0.99Mg0.01O3-δ-oxygen ionic conductors

  • 期刊论文

  • 发表日期：

    2025年10月22日

查看全文
  • Minghui Kong,
  • Haodong Pan,
  • Wenlong Wang,
  • Jiaqiang Li,
  • Qiang Yang,
  • Runru Liu,
  • Dejun Wang

摘要

Building upon the Na0.5Bi0.49-xCaxTi0.99Mg0.01O3-δ system previously reported for its optimal electrical performance, we synthesized a series of calcium-doped ceramics with compositions Na0.5Bi0.49-xCax- Ti0.99Mg0.01O3-δ (x = 0, 0.01, 0.02, 0.03) using the solid-phase method. The ceramics underwent precisely controlled two-step thermal processing: initial calcination at 800 °C followed by sintering at 1000 °C, with rigorous stoichiometric control maintained across all samples. The samples were characterized by XRD, SEM, and AC impedance spectroscopy to study the effect of Ca2+ doping concentration on the crystal structure, morphology and electrical properties of samples, specially, the bulk conductivity ( \(\sigma_b\) σ b ), grain boundaries conductivity ( \(\sigma gb\) σ g b ), and total conductivity ( \(\sigma_{t}\) σ t ), which obtained by the fitted impedance spectra, were analyzed in detail to reveal the effect of Ca2+-doping on the electrical performance. The findings revealed that all the samples displayed a pure perovskite phase without discernible impurity peaks. Furthermore, the average grain size of the samples decreased as the doping concentration was increased, suggesting that Ca2+ play a role in retarding grain growth. Upon substitution of Bi3+ with Ca2+, the grain conductivity peaked at a doping ratio of x = 0.02. The grain boundary conductivity, on the other hand, increased initially with the rise in x before declining, reaching its maximum at x = 0.01. Consequently, the total conductivity was found to be at its highest when x = 0.01.