Preparation and Dielectric Properties of Co Contained Unfilled Tungsten Bronze Ceramics Ba4RCo0.5Nb9.5O30

Abstract In this study, Ba4RCo0.5Nb9.5O30 (R = La, Nd, Sm, Eu) (BRCN) ceramics were synthesized using a high-temperature solid-state reaction. The effects of rare-earth ions with different ionic radii at A sites on the phase structure, microstructure, and dielectric properties of ceramics have been systematically studied. The full profile refinement XRD results show that all ceramic samples are tetragonal tungsten bronze (TTB). As the radius of the rare-earth ions decreases, the relaxation ferroelectric phase transition transforms into the dispersed phase transition, and the frequency dispersion of the ceramic samples gradually decreases. The high-frequency shift of Raman peak indicates that lattice distortion is severe. P-E loops under maximum applied electric field showed that BRCN ceramics can be used for energy storage.