Enhanced dielectric properties and chemical bond characteristics of ZnNb2O6 ceramics due to zinc oxide doping

Abstract Regarding advanced 5G mobile communication, microwave dielectric ceramics are considered as the most potential materials to develop new-generation base station resonators. Herein, ZnNb2O6 ceramics with er of approximately 24 have been prepared using the solid-state reaction method, with tailored extra ZnO of x mol% (x = 1, 2 and 3). We have for the first time applied the P-V-L chemical bond theory to investigate ZnNb2O6 ceramics with ZnO doping, by exploring the relationship of dielectric properties and chemical bond characteristics. Particularly, the Raman spectra demonstrates that the full width at half maximum of υ1 (Ag) vibration mode can exhibit significant correlation with the quality factor (Q × f ). To further support the experimental study, we have also conducted the first-principle calculation of electron density difference via CASTEP package, which further confirms the change of temperature coefficient of resonance frequency (τf ). Our newly designed ZnNb2O6 ceramics doped with 1 mol% ZnO exhibit excellent dielectric properties, i.e., er = 23.74, Q × f = 102,824 GHz and τf = −55.38 ppm/°C, which demonstrates great potential to construct miniaturized 5G base station with advanced ceramic dielectrics.