Effects of B2O3 addition on sintering behavior and microwave dielectric properties of ixiolite-structure ZnTiNb2O8 ceramics

Abstract

The effects of B2O3 additives on the sintering behavior, microstructure and microwave dielectric properties of ixiolite-structure ZnTiNb2O8 ceramics prepared by conventional solid-state route were investigated. The B2O3 additives, acting as a sintering aid, can effectively decrease the sintering temperature of ZnTiNb2O8 ceramics to 1050 °C, due to the formation of liquid phase. Little second phase from XRD results was observed throughout the entire experiments. The variations in the dielectric constant (εr) and quality factor (Q·f) of the ixiolite-structure ZnTiNb2O8 ceramics were studied systematically depending on the adopting of B2O3 and the sintering temperatures. With the increase of the B2O3 addition, εr and Q·f decreased and the temperature coefficient of resonant frequency (τf) slightly fluctuated around −20 ppm/°C. The optimal microwave dielectric properties with high εr ∼35.04, Q·f ∼50,100 GHz, and a near-zero τf ∼−20.21 ppm/°C were obtained at 1 wt%-B2O3-doped samples sintered at 1050 °C. The relatively low sintering temperature and high dielectric properties in microwave range would make ZnTiNb2O8 ceramics promising for application in electronics.