Effects of LiMoVO6 on phase composition and microwave dielectric properties of ultra-low firing Al2Mo3O12 ceramics

• Published in: Journal of materials science. Materials in electronics 2024-06, Vol.35 (18), p.1253, Article 1253
• Main Authors: Gao, Dawei, Ma, Juncheng, Zhang, Jiafen, Shi, Qingang, Yang, Hongyu, Xiong, Zhe, Zhang, Xing, Tang, Bin
• Format: Article
• Language: English
• Subjects: Ceramics; Characterization and Evaluation of Materials; Chemical compatibility; Chemistry and Materials Science; Dielectric polarization; Dielectric properties; Grain boundaries; Grain growth; Materials Science; Optical and Electronic Materials; Phase composition; Specific gravity; Temperature compensation
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-024-13076-4

In this work, reducing sintering temperature while synergistically improving temperature stability in Al 2 Mo 3 O 12 ceramic has been achieved with the assistance of the LiMoVO 6 phase. The LiMoVO 6 does not react with the Al 2 Mo 3 O 12 phase, showing excellent chemical compatibility. Both intrinsic and extrinsic factors contribute to the development of microwave dielectric properties of (1- x )Al 2 Mo 3 O 12 - x LiMoVO 6 ( x  = 0.205) ceramic. Dielectric polarization, relative density, phase constitutions, and contents greatly influence the change of ε r value; while the Q  ×  f value is more sensitive to the technological process for the solid-state method inevitably introducing grain growth and grain boundaries, resulting in grain boundary losses. Benefitting from the temperature compensation effect of the LiMoVO 6 phase, the τ f value can be effectively regulated based on the mixture rule. When sintered at 600 °C, the (1- x )Al 2 Mo 3 O 12 - x LiMoVO 6 ( x  = 0.205) ceramic shows a low ε r value of 7.05, a Q  ×  f value of about 8543 GHz (@13.4 GHz), and a τ f value of ca. − 14.2 ppm/ o C, which is suitable for applying in ULTCC technology.