Synthesis, characterization, and microwave dielectric properties of ternary-phase ixiolite-structure MgTiNb2O8 ceramics

• The ternary-phase nanosized MgTiNb2O8 powders were obtained at 800 °C by the aqueous sol–gel process.
• The ixiolite-structure MgTiNb2O8 ceramics were sintered at 1000 °C for 4 h.
• The microwave properties were εr=33.8, Q·ƒ =26,200 GHz and τƒ= −19.2 ppm/°C.

A kind of dielectric ceramic based on ixiolite-structure MgTiNb2O8 was prepared by the aqueous sol–gel process. Highly reactive nano-sized MgTiNb2O8 powders with particle sizes of 20–50 nm were successfully obtained at 800 °C as precursors. Sintering characteristics and microwave dielectric properties of MgTiNb2O8 ceramics were studied depending on sintering temperatures in the range of 900–1100 °C. With the increase of sintering temperature, density, εr and Q·ƒ values were increased and saturated at 1000 °C with excellent microwave properties with an εr of 33.8, a high Q·ƒ of 26,260 GHz, and a τf of −19.2 ppm/°C. The relatively low sintering temperature and high dielectric properties would make these ceramics promising for applications in electronics.