A microwave dielectric material Mg0.5Zn0.5ZrNb2O8

• A high quality material Mg0.5Zn0.5ZrNb2O8 was reported for the first time.
• The correlation between microwave dielectric properties and structure was discussed.
• The typical values of ε=27.06, Qf=91,077 GHz, τf=−18×10−6/°C were obtained.

A high quality microwave dielectric material Mg0.5Zn0.5ZrNb2O8 was reported in this paper. Single-phase Mg0.5Zn0.5ZrNb2O8 was prepared by a conventional mixed-oxide route and sintered in the temperature range of 1220−1300 °C. The microstructure and microwave dielectric properties were investigated systematically. The X-ray diffraction results showed that all samples exhibit a single monoclinic structure. The variation trend of dielectric constant was in accordance with that of relative density. The Qf value mainly depended on the crystal structure, and it increased with the increasing packing fraction. The temperature coefficient of τf correlated with the variation of bond valence of B-site. In summary, the monoclinic structure Mg0.5Zn0.5ZrNb2O8 ceramic samples sintered at 1260 °C exhibited uniform and dense microstructural morphology, and owned outstanding microwave dielectric properties of ε=27.06, Qf=91077 GHz, τf=−18×10−6/°C. These represent very promising candidates for the application of highly selective microwave ceramic resonators and filters.