Phase Evolution, Microstructure, and Microwave Dielectric Properties of Reaction-Sintered Li2ZnTi3O8 Ceramic Obtained Using Nanosized TiO2 Reagent

Dielectric ceramics in the Li2ZnTi3O8 system were synthesized using TiO2 nanoparticle reagent by the reaction-sintering process. The special effects of the TiO2 nanoparticle reagent on the densification, phase distribution, microstructure, and dielectric properties were characterized using powder x-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). A single phase of Li2ZnTi3O8 ceramic was confirmed by the XRD pattern at all temperatures except 1075°C. The reaction between the starting materials was accelerated using TiO2 nanoparticles, with pure Li2ZnTi3O8 phase being created even at low sintering temperature of 900°C, along with increasing green specimen density at the compaction stage. The presence of TiO2 phase in the Li2ZnTi3O8 ceramic improved the \(\tau_\text{f}\) value and shifted it to near zero at 1075°C, and the ceramic exhibited excellent microwave dielectric properties of \(\varepsilon_\text{r}\) = 23.5, \(Q \times f\) = 71,000 GHz, and \(\tau_\text{f}\) = −3.5 ppm/°C.