Low-temperature synthesis and microwave dielectric properties of trirutile-structure MgTa2O6 ceramics by aqueous sol–gel process

Trirutile-structure MgTa2O6 ceramics were prepared by aqueous sol–gel method and microwave dielectric properties were investigated. Highly reactive nanosized MgTa2O6 powders were successfully synthesized at 500 °C in oxygen atmosphere with particle sizes of 20–40 nm. The evolution of phase formation was detected by DTA–TG and XRD. Sintering characteristic and microwave dielectric properties of MgTa2O6 ceramics were studied at different temperatures ranging from 1100 to 1300 °C. With the increase of sintering temperature, density, ɛr and Q · f values increased and saturated at 1200 °C with excellent microwave properties of ɛr ∼ 30.1, Q · f ∼ 57,300 GHz and τf ∼ 29 ppm/°C. The sintering temperature of MgTa2O6 ceramics was significantly reduced by aqueous sol–gel process compared to conventional solid-state method.