Bond analysis of novel MnZrTa2O8 microwave dielectric ceramics with monoclinic structure.

Zhang, Yun; Ding, Shihua; Li, Chao; Song, Tianxiu; Zhang, Yingchun

A new type of ceramic, namely MnZrTa2O8, was synthesized after sintering at high temperature in this work. The possible dielectric loss mechanism was discussed by Raman spectroscopy and chemical bond theory. X-ray diffraction indicated that MnZrTa2O8 formed through a reaction between ZrO2 and intermediate MnTa2O6. After sintering at 1350 °C, a monoclinic structure with cell parameters a = 4.8370(3) Å, b = 5.7163(1) Å, c = 5.1398(5) Å, β = 91.7219° was gained for ceramic. Among all bonds, Ta–O with the greatest bond ionicity and lattice energy was the dominant factor that influenced the microwave dielectric properties. The temperature coefficient of the resonant frequency τf changed from − 50.55 to − 41.21 ppm/ °C, which was related to the lattice energy. The effect of porosity on dielectric loss was also checked and found to be significant. MnZrTa2O8 ceramic exhibited relative permittivity εr ~ 23.0 and enhanced quality factor Q × f~48103 GHz (at 8.97 GHz), which provided a promising candidate for electric components.

PERMITTIVITY; DIELECTRIC loss; QUALITY factor; DIELECTRIC properties; CERAMICS; DIELECTRICS; MICROWAVE sintering

Journal of Materials Science, 2020, Vol 55, Issue 20, p8491

0022-2461

Academic Journal

10.1007/s10853-020-04629-z