High permittivity and low loss dielectric ceramics Ba5LnNiNb9O30 (Ln = La, Nd and Sm)

Three novel Ba5LnNiNb9O30 (Ln = La, Nd and Sm) ceramics were prepared and characterized in the BaO-Ln2O3-NiO-Nb2O5 system. All three compounds are paraelectric phases adopting the filled tetragonal tungsten bronze (TB) structure at room temperature. At 1 MHz, Ba5LnNiNb9O30 ceramics have a high dielectric constants in the range 193-245.3, a low dielectric loss in range 0.0059-0.0087, and the temperature coefficients of the dielectric constant (τɛ) in the range −1140 to −1310 ppm °C−1.