Microwave dielectric ceramics with the composition of Li2ZnTi3O8 – 4 wt% TiO2 were synthesized by the conventional solid‐state reaction. 4 wt% TiO2 powders with different particles size were added to the Li2ZnTi3O8 ceramic. Then the ceramic samples were sintered at temperatures 1075°C, 1050°C, 1000°C, and 950°C for 4 h. The effect of the particles size of TiO2 additive on the microwave dielectric properties of the ceramics has been investigated. In the study two categories of particles size of TiO2 additive have been used; (i) Nanoparticle (50 nm), (ii) Micron sized (40, 5, 1 μm) powder. X‐ray showed that the TiO2 additive has not solved in the LZT structure and has not almost undergone chemical reaction with the LZT ceramic. The results showed that the addition of TiO2 nanoparticles to the LZT ceramics significantly improved the density and a dense and uniform microstructure and also abnormal grain growth were observed by SEM. The use of TiO2 nanoparticle reduces porosity and leads to an increase in green density. The maximum density was found to be 98.5% of the theoretical density and the best relative permittivity of 28, quality factor of 68000 GHz and τf value of −2 ppm/°C were obtained for the samples added with 4 wt% of the TiO2 nanoparticles, sintered at 1050°C for 4 h.

Dielectric ceramics in the Li 2 ZnTi 3 O 8 system were synthesized using TiO 2 nanoparticle reagent by the reaction-sintering process. The special effects of the TiO 2 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 Li 2 ZnTi 3 O 8 ceramic was confirmed by the XRD pattern at all temperatures except 1075°C. The reaction between the starting materials was accelerated using TiO 2 nanoparticles, with pure Li 2 ZnTi 3 O 8 phase being created even at low sintering temperature of 900°C, along with increasing green specimen density at the compaction stage. The presence of TiO 2 phase in the Li 2 ZnTi 3 O 8 ceramic improved the s f value and shifted it to near zero at 1075°C, and the ceramic exhibited excellent microwave dielectric properties of e r = 23.5, Q Â f = 71,000 GHz, and s f = À3.5 ppm/°C.

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In this study, the (Ca0.95M0.05)V2O6 (M = Zn, Ba) and the CaV2O6 ceramics were synthesized through a solid‐state reaction method, and the effects of Zn2+ and Ba2+ substitution on the structure, sintering temperature, densification, microstructure and microwave dielectric properties of CaV2O6 ceramic were analysed. The XRD patterns of the sintered samples indicated a single‐phase of CaV2O6 in all temperatures. Substitution of Zn2+ caused a lower sintering temperature and improved the densification of the CaV2O6 ceramic. While the dielectric properties of the (Ca0.95Ba0.05)V2O6 compound were not desirable, the (Ca0.95Zn0.05)V2O6 sample sintered at 650°C for 4 hours showed significant dielectric properties, with εr = 10.29, Q × f ~  53 000 GHz (at 15.5 GHz) and τf = −72.37 ppm/°C. Moreover, the chemical compatibility of the CaV2O6 ceramic with Al electrode was examined.

In the present work, the Li 2 ZnTi 3 O 8 ceramics were prepared via the solid-state reaction method, afterward annealed at 800°C in a time variation from 4 to 20 h. The ordering, microstructures and dielectric properties were investigated using x-ray diffraction, scanning electron microscopy, network analyzer, and Raman spectroscopy. The most significant enhancement of quality factor is obtained in the sample annealed for 20 h, while the dielectric constant and temperature coefficient of resonant frequency change slightly. This result mainly attributes to the enhancement of ordering, which could be related to the increase in the Zn-O bond strength in ZnO 4 tetrahedra. Meanwhile, the full-width at half-maximum of A 1g mode decreased with higher annealing time, which suggested less variation in the Zn-O bond length and a higher degree of ordering. The best combination of microwave dielectric characteristic is obtained in the sample annealed at 800°C for 20 h: Q Â f 5 112,400 GHz, e r 5 24.500, and s f 5 À11 ppm/°C.