Crystal structure, lattice vibrational characteristics, and dielectric properties of Ba(Mg1/2Mo1/2)O3 ceramics sintered at different temperatures
Crystal structure, lattice vibrational characteristics, and dielectric properties of Ba(Mg1/2Mo1/2)O3 ceramics sintered at different temperatures
复制标题
不同温度烧结Ba(Mg1/2Mo1/2)O3陶瓷的晶体结构、晶格振动特性及介电性能
DOI：
10.1016/j.materresbull.2021.111656
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发表时间：
2021
影响因子：
5.4
通讯作者：
Jing Wang
中科院分区：
文献类型：
--
作者：
Jiayu Li;Jiqing Lv;Feng Shi;Ze-Ming Qi;Runhao Han;Jing Wang
采用传统固相烧结法在不同烧结温度（Ts=1250-1325 °C）下制备了双钙钛矿结构Ba（Mg 1/2 Mo 1/2）O3（BMM）陶瓷。X射线衍射（XRD）结果表明，陶瓷为1：1有序面心立方结构（Fm-3 m），在1300 °C烧结时，陶瓷的相对密度最大。通过拉曼光谱和远红外反射光谱对晶格振动特性进行了表征。基于远红外数据，采用四参数半量子模型（FPSQ）对BMM陶瓷的本征性质进行了计算，计算结果与实测值较为接近。BMM F2 g（B）模的拉曼频移（归因于Ba原子的中心对称振动）与校正的介电常数和Ba-O键长呈负相关。随着烧结温度（Ts）的升高，相对密度与品质因子（Q×f）呈正相关，Ba-O键长的变化导致氧八面体畸变，氧八面体畸变与介电常数呈正相关。烧结温度为1300 °C时，BMM陶瓷的介电性能最好（εr= 4.987，Q ×f= 23, 069 GHz，f= 11.16GHz）。
Double perovskite structured Ba(Mg1/2Mo1/2)O3(BMM) ceramics were prepared by traditional solid sintering methods at different sintering temperatures (Ts=1250–1325 °C). X-ray diffraction (XRD) data proved a 1:1 ordered face-centered cubic lattice (Fm-3 m), and the ceramic sintered at 1300 °C obtained maximum relative density. The lattice vibration characteristics were identified by Raman spectroscopy and far-infrared reflection spectroscopy. Based on the far-infrared data, a four-parameter semi-quantum model (FPSQ) was applied to calculate the intrinsic properties of BMM ceramics, and the obtained results approximated the measured values. The Raman shift of the BMM F2g(B) mode (attributed to the centrosymmetric vibration of Ba atom) was shown to be negatively correlated with the corrected permittivity and Ba-O bond length. With increasing sintering temperature (Ts), the relative density is positively correlated with the quality factor (Q×f), and the change of Ba-O bond length leads to distortion of the oxygen octahedron, which is positively correlated with the dielectric constant. The sintered BMM ceramics obtained their best dielectric properties at 1300 °C (εr= 4.987,Q×f=23,069 GHz,f= 11.16 GHz).