Novel Raman spectroscopy of a strong high-k diffuse phase transition (Ba_{1∿span style='font-style: italic'>x}Sm_x)(Ti_{0.95∿span style='font-style: italic'>x/4}Ce_0.05)O₃ ceramics

详细信息    查看全文

• 作者：Dan-Dan Han ; Qiao-li Liu ; Yan-Dong Wang ; Chang-Hao Wang ; Da-Yong Lu ; ^{cninjp11232000@yahoo.com" class="auth_mail" title="E-mail the corresponding author} ; ^{dylu@jlict.edu.cn" class="auth_mail" title="E-mail the corresponding author}
• 关键词：B. Defects ; C. Dielectric properties ; D. BaTiO3 and titanates ; Powders ; solid state reaction and sintering
• 刊名：Ceramics International
• 出版年：2016
• 出版时间：15 May 2016
• 年：2016
• 卷：42
• 期：7
• 页码：8815-8821
• 全文大小：3631 K

文摘

Novel Raman spectra were discovered in (Ba_{1trong class="boldFont">−trong>x}Sm_x)(Ti_{0.95trong class="boldFont">−trong>x/4}Ce_0.05)O₃ (0.03≤x≤0.10) ceramics and investigated in relation to the fluorescent effect of Sm³⁺ ions. Special interest was paid to analyze the dielectric response and defect chemistry associated with the structural evolution by X-ray diffraction (XRD), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), Raman spectroscopy (RS), and dielectric measurements. Complete solid solutions, known as BS5TC5 and BS6TC5 for (Ba_{1trong class="boldFont">−trong>x}Sm_x)(Ti_{0.95trong class="boldFont">−trong>x/4}Ce_0.05)O₃ ceramics were found to form at x=0.05 and 0.06 (approximately) and exhibit a cubic structure and a non-uniform microstructure. BS6TC5 exhibited a strong high-k   diffuse phase transition (DPT) behavior (thmlsrc">title="View the MathML source" class="mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0272884216300645&_mathId=si0003.gif&_user=111111111&_pii=S0272884216300645&_rdoc=1&_issn=02728842&md5=74582dabb24de1d7399948fbb490bc34">t="11" width="11" alt="View the MathML source" style="margin-top: -5px; vertical-align: middle" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S0272884216300645-si0003.gif">t>t="11" border="0" style="vertical-align:bottom" width="11" alt="View the MathML source" title="View the MathML source" src="http://origin-ars.els-cdn.com/content/image/1-s2.0-S0272884216300645-si0003.gif">t>thContainer hidden">thCode">th altimg="si0003.gif" overflow="scroll">tshift="90%" superscriptshift="100%">ϵthvariant="normal">mt="true" form="prefix">′th>=9300, T_C=78 °C), a lower dielectric loss (tan δ<0.05), and a feature of mixed valence at Ba sites (Sm³⁺, Ce³⁺) and Ti sites (Sm³⁺, Ce⁴⁺). The BSTC ceramics with x=0.09 met the Y5V specification. A weak g=2.004 EPR signal associated with ionized Ti-vacancy defects appeared in single-phase ceramics.