Effect of TiO2 Ratio on the Phase and Microwave Dielectric Properties of Li2ZnTi3+xO8+2x Ceramics

Low-loss materials Li2ZnTi3+xO8+2x (LZT) (x = 0, 0.10, 0.17, 0.25, 1.00) were prepared by the conventional solid-state route. The effect of TiO2 ratio on phase composition, microstructure, and the microwave dielectric properties of Li2ZnTi3+xO8+2x ceramics were investigated using x-ray diffraction, scanning electron microscopy, energy-dispersive x-ray spectroscopy, and Vector Network Analyzer. The results revealed that a two-phase system Li2ZnTi3O8-TiO2 was formed. The appropriate content of TiO2 ratio can effectively adjust the temperature coefficient of the resonant frequency (τf) value from −14.5 to 0 ppm/ °C without obvious degradation of the microwave dielectric properties. The microwave dielectric properties of the Li2ZnTi3+xO8+2x materials were characterized at microwave frequencies. Typically, the Li2ZnTi3+xO8+2x (x = 0.17) ceramic sintered at 1,160 °C for 5 h showed excellent microwave dielectric properties with εr = 28.51, Q × f = 58,511 GHz, and τf = + 2.3 ppm/ °C.