Dielectric properties of ZnNb2O6-ZnTiNb2O8 composites for microwave applications

In this study, the dielectric properties were evaluated in the microwave region for a ZnNb2O6 (ZNO) matrix with added TiO2. X-ray diffraction analysis demonstrated that the addition of TiO2 to ZNO led to formation of the ZnTiNb2O8 (ZTNO) phase. Evaluation of the dielectric properties in the microwave region for the ZNO-ZTNO ceramic composites showed that the permittivity (epsilon r) ranged between 23.08 and 26.19 and the dielectric loss (tan delta) was 7.20 x 10-5 to 3.25 x 10-4. The temperature coefficient of resonant frequency (tau f) ranged from-97.64 ppm degrees C- 1 to-62.93 ppm degrees C- 1, thereby demonstrating that adding TiO2 increased the tau fvalue. The ZNO-ZTNO composites were evaluated as dielectric resonator antennas and their far-field parameters obtained based on numerical simulations indicated a gain between 4.69 and 5.60 dBi, bandwidth of 125.00-164.00 MHz, and efficiency above 98%. These results demonstrate that the ceramics investigated in this study have great potential for application in devices that operate in the C-band.

Automated summary

This study evaluated the dielectric properties of a ZnNb2O6 matrix with added TiO2 in the microwave region. The addition of TiO2 led to the formation of the ZnTiNb2O8 phase. The ZNO-ZTNO composites showed improved resonant frequency coefficient, and as dielectric resonator antennas, exhibited high gain, bandwidth, and efficiency.