Microwave dielectric properties of temperature stable (1 − x)BaCaV2O7–xTiO2 composite ceramics

Abstract

The microwave dielectric properties of (1 − x)BaCaV2O7–xTiO2 (x = 0, 0.1, 0.2, 0.4 and 0.5) ceramics prepared by the solid-state reaction route were investigated. Effects of TiO2 addition on the sintering behavior, crystal structure, microstructure, and microwave dielectric properties of BaCaV2O7 were studied. X-ray diffraction analysis indicates the coexistence of rutile TiO2 and BaCaV2O7 phase when sintered at 950 °C. Both the relative permittivity and the temperature coefficient of resonant frequency increased obviously as x value increased from 0 to 0.5. A composite ceramic 0.5BaCaV2O7–0.5TiO2 exhibited excellent microwave dielectric properties with a relative permittivity ~21.4, a high quality factor value of ~14,630 GHz and a near-zero temperature coefficient of resonant frequency of ~+4.04 ppm/°C.