Dielectric Nanoceramics for S-Band Applications: Zinc Aluminate Enhanced with Titanium and Magnesium

Abstract A straightforward sol-gel technique was used to prepare a nanoceramic composite material consisting of 89Wt%(ZnAl₂O₄TiO₂) and 11Wt%MgTiO₃ (ZTMg), designed to enhance dielectric properties for miniature patch antennas in wireless applications. X-ray diffraction (XRD) analysis revealed anatase-rutile phases in TiO₂, a wurtzite hexagonal shape in ZnAl₂O₄ (Gahnite), and MgTi₂O₅ phases. Raman spectroscopy identified distinct vibration modes corresponding to ZnO at 346 cm⁻¹ and TiO₂ at 717 cm⁻¹. The morphological structure of ZTMg was examined using field emission scanning electron microscopy (FESEM), showing the formation of agglomerated spherical nanoparticles. Energy-dispersive X-ray spectroscopy (EDS) displayed elemental peaks of Zn, Ti, Al, O, and Mg. The calculated mean grain size was 19.26 nm. The conductivity of the ZTMg nanoceramic composite material increased with frequency at various temperatures. As the operating frequency rose, the nanoceramic composite dielectric material exhibited commendable dielectric properties ranging from 13.46 to 19.39, with a reduced dielectric loss (0.25–0.64) in the temperature range of 30–150°C, making it suitable for microwave applications. The fabricated prototype antenna showed excellent performance in both measured and simulated results, with return loss (RL) values of -20.51/-12.53 dB, bandwidth (BW) of 1.36/2.02 GHz, and resonant frequency (fr) of 3.25/3.30 GHz.