Large electrocaloric effect in (Bi0.5Na0.5)0.94Ba0.06TiO3 lead-free ferroelectric ceramics by La2O3 addition

Abstract Large electrocaloric effect is observed in La doped (Bi 0.5 Na 0.5 ) 0.94 Ba 0.06 TiO 3 lead-free ferroelectric ceramics synthesized by conventional solid state reaction. The dielectric permittivity and ferroelectric hysteresis loops are measured. The indirect method is used to calculate electrocaloric temperature change of BNBT6 doped by La. The introduction of La 2 O 3 can enhance the electrocaloric effect of BNBT6. The largest temperature change |Δ T 62 | = 2.61 K and electrocaloric coefficient | ξ max | = 0.052 Kcm/kV is achieved in the 0.5 wt% La doped BNBT6, which is significantly higher than that of BNT-based and lead-containing ferroelectric materials reported so far. For 1 wt% ones, the |Δ T 30 | = 1.954K and | ξ max | = 0.039 Kcm/kV is obtained in the room-temperature, which promises the environmental-friendly La doped BNBT6 is candidate for applications of solid state cooling devices.