Crystal structure, bond characterization and lattice energy of B-site 1:3 ordering inverse spinel Li1.25Ga0.25Ti1.5O4 ceramic

作者：Zhang, Ning; Chen, Junqi; Zhang, Yuheng; Xiang, Huaicheng; Tang, Ying^*; Fang, Liang

来源：Ceramics International, 2024, 50(1): 126-133.

DOI：10.1016/j.ceramint.2023.10.030

• Microwave dielectric properties
• Ordered spinel
• Bond valence
• Ionic polarizability
• P-V-L theory

In this work, inverse spinel structured Li1.25Ga0.25Ti1.5O4 ceramics with a space group of P4332 were synthesized by a solid-state reaction method. XRD, SAED, HRTEM, and Raman spectra analysis demonstrated that the Li1.25Ga0.25Ti1.5O4 ceramic was formed a A-site 1:3 disordered and B-site 1:3 ordered spinel structured. A high relative density (98.7%) with excellent microwave dielectric properties of Er = 23.8, Qxf = 93,800 GHz, and zf = -21.9 ppm/oC were obtained in 1110 degrees C for 4 h. Bond valence analysis demonstrated that the average cations of Li1.25Ga0.25Ti1.5O4 were in the rattling state, and the polarizability of Ti4+ was underestimated. The P-V-L chemical bond theory and lattice energy analysis results indicated that B-O bonds were the main factor to affect the Er and Q x f, and the under-bonding Ti4+and Ga3+ has a significant effect on the zf. All the results show that the Li1.25Ga0.25Ti1.5O4 ceramic might be a potential candidate for 5 G communication technology.

• 单位
  桂林航天工业学院; 广西大学; y; 桂林理工大学