Permittivity of citrate sol-gel derived Bi2Ti4O11 dielectric ceramics
Permittivity of citrate sol-gel derived Bi2Ti4O11 dielectric ceramics
复制标题
柠檬酸盐溶胶-凝胶衍生的 Bi2Ti4O11 介电陶瓷的介电常数
DOI：
10.1016/j.ceramint.2015.04.137
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发表时间：
2015
影响因子：
5.2
通讯作者：
Xiang Maoqiao
中科院分区：
文献类型：
--
作者：
Zhang Yun;Zhang Yingchun;Fu Baojian;Hong Ming;Xiang Maoqiao
采用改进的溶胶-凝胶法合成了Bi 2 Ti4 O 11微波介质陶瓷。采用差热分析（DTA）/热重分析（TG）对前驱体的热分解行为进行了表征。基于XRD结果，可以得出结论，Bi 2 Ti4 O 11在约678 °C开始通过TiO 2与中间相Bi 2 Ti 2 O 7反应而形成。在750 °C下煅烧干凝胶，得到了球形均匀的Bi 2 Ti4 O 11颗粒。不同烧结温度下的XRD图谱证实了Bi_2Ti_4O_（11）单相的形成。体积密度、离子极化率和显微结构对Bi 2 Ti4 O 11陶瓷的微波介电性能有很大影响。在1050 °C烧结的Bi 2 Ti4 O 11样品的最大相对密度达到97.39%，具有优良的微波介电性能，其ε r为52.35，Q × f为4850 GHz，τ f为−350 ppm/°C，有望在军用微波雷达、介质谐振器和移动的通信基站等领域得到应用。
Bi2Ti4O11microwave dielectric ceramics were synthesized by a modified sol–gel route. The thermal decomposition behavior of the as-prepared precursors was characterized by differential thermal analysis (DTA)/thermogravimetry (TG). Based on the XRD results, it could be concluded that Bi2Ti4O11began to form at around 678 °C by the reaction of TiO2with intermediate phase Bi2Ti2O7. Bi2Ti4O11particles with uniform spherical shape were obtained by calcining the xerogel at 750 °C. XRD patterns of the ceramics sintered at various temperatures confirmed the formation of single Bi2Ti4O11phase with monoclinic structure. The microwave dielectric properties of Bi2Ti4O11ceramics were considerably affected by bulk density, ionic polarizability and microstructure. The Bi2Ti4O11samples sintered at 1050 °C reached the maximum relative density of 97.39% and possessed excellent microwave dielectric property withεrof 52.35, a highQ×fof 4850 GHz, and aτfof −350 ppm/°C, making them promising for applications in military microwave radar, dielectric resonator and mobile communication base station.