Amelioration of sintering and multi-frequency dielectric properties of Mg3B2O6: A mechanism study of nickel substitution using DFT calculation

• 作者: Rui PENG Yongcheng LU Qin ZHANG Yuanming LAI Guoliang YU Xiaohui WU Yuanxun LI Hua SU Huaiwu ZHANG
• 来源期刊: 先进陶瓷（英文版）
• 年，卷（期）: 2021,（6）
• 所属期刊栏目: Research Article
• 页码范围: 1398-1407
• 页数: 10页
• 语种: 英文

摘要

With the support of density functional theory (DFT) calculation, the amelioration of sintering and dielectric properties of the Mg3B2O6 (MBO) ceramic was realized through the substitution of magnesium with nickel. The TE-mode cylindrical cavity method was used to measure the dielectric properties at different frequencies. The thermo-mechanical analysis and simultaneous thermal analysis were used to characterize the chemical and mechanical properties. The phase composition was determined through the X-ray diffraction (XRD) and Raman spectrum. The microstructure was investigated using the scanning electron microscopy (SEM). Magnesium substitution with nickel (4 mol％) could ionize the B–O bond of BO3, modify the vibration mode, improve the order degree, densify the microstructure, decrease the intrinsic densification temperature, and ameliorate the dielectric properties of the MBO ceramics. The maximum values were achieved for the ceramics with 4 mol％ nickel and sintered at 1175℃ , that is, 97.2％ for relative density, 72,600 GHz (10 GHz), 75,600 GHz (11.4 GHz), and 92,200 GHz (15 GHz) forQ × f, 7.1 (10 GHz), 7.01 (11.4 GHz), and 6.91 (15 GHz) forεr, and?56.3 ppm/℃ forτf.