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An ultrahigh-temperature X – R type dielectric material, BaTiO 3 –Na 0.5 Bi 0.5 TiO 3 –Nb 2 O 5 –ZnO–Glass with Sm 2 O 3 addition, was successfully prepared. The effects of Sm 2 O 3 content on the phase structure, dielectric and electric properties of ceramics were investigated. Sm ion can substitute for both Ti and Ba-sites, which leads to the decrease of spontaneous polarization and dipolar polarization. As a result, the temperature stability in e r of sample is improved obviously. The 0.2 mol% Sm 2 O 3 -doped sample shows the optimal dielectric properties ( e r =2458; tan δ =1.80%; ∆ C / C 20 °C X – R specification. This material with particular focuses on enhancing the upper temperature limit to 450 °C, while still maintaining high dielectric constant.

A lead-free, high-permittivity and high-temperature X–R type dielectric material was successfully prepared in ZnO-doped BaTiO 3 -Na 0.5 Bi 0.5 TiO 3 -Nb 2 O 5 (BNN)- based system. The effects of ZnO content on the phase structure, electric and dielectric properties of the ceramics were investigated. Results indicate that ZnO addition plays a critical role in increasing permittivity and improving the temperature stability. The 5 wt% ZnO-doped sample shows the optimal dielectric performance ( e r =2404; tanδ=1.76%; ΔC/C 20 °C