Tunable electrocaloric and energy storage behavior in the Ce, Mn hybrid doped BaTiO3 ceramics

The electrocaloric effect and energy storage property are tuned in the Ba1-xCexTi0.99Mn0.01O3 ceramics prepared by the solid state reaction method. The ceramics with lower Ce content (x = 0.005, 0.015) show a better ΔT and ΔT/ΔE response. The ceramics with higher Ce content (x = 0.030, 0.040, 0.045) represent the broader ΔT peaks (50 K-60 K), and the higher energy storage density and efficiency. The largest electrocaloric response (ΔTmax = 1.22 K, ΔT/ΔE = 0.41 K mm/kV) is found in the Ba0.995Ce0.005Ti0.99Mn0.01O3 ceramics, which is comparable or even higher than that of the most isovalent substituting BaTiO3-based ceramics reported before. The maximum energy storage density 0.11 J/cm3 (E = 30 kV/cm) is obtained for the Ba0.970Ce0.030Ti0.99Mn0.01O3 ceramics, with high efficiency of 65-88% over a wide temperature range of 72 K. This work may open more opportunities to design high electrocalaric and energy storage performance lead-free systems from the viewpoint of the heterovalent and size mismatch substitution.