Improvement of solid solution and dielectric properties of (Ba,Sr)(Ti,Ce)O3 ceramics by slight La doping

Sr and Ce co-doped BaTiO3 ceramics prepared by the cold-pressing ceramic process exhibited a worse solid solution. The influence of slight La doping on solid solution and dielectric properties of (Ba,Sr)(Ti,Ce)O3 ceramics (BSTC) was investigated by XRD, SEM, and dielectric measurements. The results indicated that La addition to BSTC may form a single-phase solid solution up to 15% Sr and result in a grain-size refinement (< 1 μm). The most marked effect is strong broadening and rise of Curie peak around room temperature and a dramatic dielectric-peak shift rate of -56°C/at.% La for dense (Ba1-x-zSrxLaz) (Ti1-z/4-yCey)O3 (x = 0.10, y = 0.03, z = 0.01) ceramic with higher room-temperature dielectric permittivity (∼3500) and lower dielectric loss (< 0.02).