Yao Yang, Wang Yuanyuan, Bafrooei Hadi Barzegar, Mao Minmin, Liu Bing, Lu Zhilun, Lin Huixing, Spreitzer Matjaz, Wang Dawei, Zheng Xinghua, Song Kaixin
College of Electronic Information, Hangzhou Dianzi University, Hangzhou 310018, China.
School of Chemical and Process Engineering, University of Leeds, Leeds LS2 9JT, U.K.
Inorg Chem. 2024 May 27;63(21):10022-10030. doi: 10.1021/acs.inorgchem.4c01273. Epub 2024 May 15.
In this work, phase-pure Mg(NiCo)AlSiO (0 ≤ ≤ 1) ceramics were synthesized by a high-temperature solid-state method. On the basis of Rietveld refinement data of X-ray powder diffraction and Phillips-Vechten-Levine theory, the atomic ionicity, lattice energy, and bond energy of the compound were calculated to explore their influence on the microwave dielectric properties of ceramics. The MgNiCoAlSiO ( = 0.5) ceramic exhibited the best microwave dielectric properties: = 4.44, = 73 539 GHz@13 GHz, and τ = -23.9 ppm/°C. (NiCo) complex ionic doping, compared with only Ni or Co, is beneficial for improving the symmetry of [SiAlO] hexagonal rings and reducing distortion. Subsequently, 8 wt % TiO was added to MgNiCoAlSiO, resulting in a near-zero and high values for the composite ceramic, with = 5.22, = 58 449 GHz@13 GHz, and τ = -2.06 ppm/°C. Finally, a 5G millimeter-wave antenna with a central operating frequency of 25.52 GHz was designed and fabricated using the MgNiCoAlSiO-8 wt % TiO ceramics. Operating in the 24.7-26.0 GHz range, it demonstrated favorable radiation characteristics with a simulated efficiency of 85.2% and a gain of 4.58 dBi. The antenna's performance confirms the high potential of the cordierite composite for application in 5G communication systems.
