Crystal structure, chemical bonds, and microwave dielectric properties of NaZnPO4 ceramic

This study reports the synthesis of NaZnPO 4 ceramics using the solid-state reaction method and investigates their microwave dielectric properties for the first time. XRD analysis confirmed the formation of single-phase NaZnPO 4 ceramic with a monoclinic structure. Among the samples, the one sintered at 850 °C exhibited the highest relative density of 95.4 % and demonstrated excellent microwave dielectric properties, including a ε r of 6.4, a Q × f of 49,500 GHz, and a τ f of −47.3 ppm/°C. The measured ε r values closely aligned with theoretical predictions, suggesting that molecular polarization significantly influences the relative dielectric constant. Furthermore, variations in sintering temperature primarily affected ε r and Q × f through changes in relative density. Utilizing the P-V-L theory, we elucidated the relationship between chemical bond parameters and microwave dielectric properties, establishing that the P-O bond plays a dominant role in the dielectric behavior of the ceramics. Additionally, Raman spectroscopy results indicated that P-O bond vibrations predominated the entire spectrum.