Low temperature sintering and microwave dielectric properties of Li2O–3ZnO–5TiO2 ceramics doped with V2O5

Novel low-temperature sinterable Li2O–3ZnO–5TiO2 (LZT135) ceramics were prepared through a solid-state reaction method. XRD and EDS results showed that the LZT135 ceramics formed solid solutions with a crystal structure similar to Zn2Ti3O8. The addition of V2O5 could decrease the sintering temperature of LZT135 ceramics to about 900 °C. When 0.6 wt% V2O5 was added, the LZT135 ceramics exhibited dielectric properties with relative permittivity (εr) = 20.2, quality factor (Q×f) = 59,000 GHz, and temperature coefficient of resonant frequency (τf) = − 30.2 ppm/°C at a sintering temperature of 900 °C. However, the τf value was still too high for industrial applications; therefore, TiO2 was added to the LZT135 ceramics to further adjust the τf value. Finally, near-zero τf values and simultaneously desirable Q×f values were maintained for the low-temperature sintered LZT135 ceramics. The LZT135 ceramics doped with 0.6 wt% V2O5 and 6 wt% TiO2 exhibited reasonably good microwave dielectric properties with εr = 24.3, Q×f = 51,700 GHz, and τf = 0.3 ppm/°C when sintered at 900 °C, thus showing a great potential for low-temperature co-firing ceramic applications.