Synthesis, characterization, and microwave dielectric properties of ixiolite-structure ZnTiNb2O8 ceramics through the aqueous sol-gel process

Microwave dielectric ceramics based on ixiolite-structure ZnTiNb2O8 were prepared by an aqueous sol-gel process. Highly reactive nanosized ZnTiNb2O8 powders with particle sizes of 30-50 nm were successfully obtained at 700 °C as precursors. Sintering characteristics and microwave dielectric properties of ZnTiNb2O8 ceramics were studied depending on sintering temperatures ranging from 950 °C to 1100 °C. The dielectric properties were strongly dependent on the compositions, the densifications and the microstructures of the specimens. With the increase of sintering temperature, density, εr and Q ⋅ f values were increased and saturated at 1050 °C with excellent microwave properties with an εr of 35.3, an high Q ⋅ f of 66,700 GHz, and a τf of −55.4 ppm/°C. The correlations of microstructure and dielectric properties for ZnTiNb2O8 ceramics were also investigated. The relatively low sintering temperature and high dielectric properties in microwave range would make these ceramics promising for application in electronics.