The microwave dielectric properties of the low-temperature firing BaZnP2O7 ceramics with Co2+ substitution

In this study, the microwave dielectric properties of Co2+-substituted BaZnP2O7 ceramics prepared through conventional solid-state synthesis were investigated. X-ray diffraction, Rietveld refinement, energy-dispersive spectroscopy, and Raman spectroscopy all indicated that BaZn1-xCoxP2O7 ceramics sintered at 875 degrees C were composed of a single phase. The lattice strain and crystallite size were estimated using Williamson-Hall (W-H) method. Both the scanning electron microscopy images and density measurements showed that Co2+ ions had an effect on the grain growth and densification of ceramics. The microwave dielectric properties were influenced by the intrinsic and extrinsic factors that varied with the increase of x value. An optimal performance (epsilon(r) = 7.62, Q x f = 600 45 GHz, and tau(f) = -74 ppm/degrees C) was achieved at x = .01. The porosity and relative density played a significant role in the dielectric constant epsilon(r): the denser the ceramic structure, the larger the dielectric constant. The Q x f and tau(f) values were negatively correlated with the full width at half maximum of the Raman vibrational peak at approximately 1049 cm(-1). Moreover, the Q x f value was improved compared to that of the undoped BaZnP2O7 ceramics. Therefore, cobalt ion substitution is an effective strategy to enhance the performance of microwave dielectric ceramics.