Characterization of low loss microwave dielectric materials Zn_0.92Co_0.08ZrNb₂O₈ based on the complex chemical bond theory

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• 作者：Z. L. Yang ; H. L. Pan ; X. S. Jiang ; H. T. Wu
• 刊名：Journal of Materials Science: Materials in Electronics
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：28
• 期：2
• 页码：1597-1604
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Optical and Electronic Materials; Characterization and Evaluation of Materials;
• 出版者：Springer US
• ISSN：1573-482X
• 卷排序：28

文摘

Low loss microwave dielectric ceramics Zn_0.92Co_0.08ZrNb₂O₈ with wolframite structure were prepared by the solid state method. Sintering characteristics, phase composition and microwave dielectric properties were investigated systematically. X-ray diffraction results showed that all samples exhibited a wolframite structure. Rietveld refinement was used to analyze the crystal structure. Based on the lattice parameters, the bond ionicity, the lattice energy, the bond energy and the coefficient of thermal expansion were calculated to evaluate the structural characteristics. The ε_r values could be strongly dependent on the bond ionicity of the Nb–O bonds. The Q·j values were main affected by the lattice energy and the bond energy of the Nb–O bonds. As for the τ_f values, it could be mainly affected by the coefficient of thermal expansion of Zn/Co–O bonds. At the sintering temperature of 1200 °C, Zn_0.92Co_0.08ZrNb₂O₈ ceramics exhibited the excellent microwave properties of ε_r = 27.10, Q·f = 61,036 GHz (at 8.54 GHz) and τ_f = −9.81 ppm/°C. These results demonstrated that Zn_0.92Co_0.08ZrNb₂O₈ ceramics could be promising candidate materials for the application of highly selective microwave ceramic resonators and filters.