No abstract

Lead-free perovskite materials with high performance have high potential in clean energy storage applications and developments of electrocaloric devices. In this work, we report structural, dielectric, ferroelectric properties, energy storage and electrocaloric effectnear the ambient temperature in barium stannate titanate (BaTi0.89Sn0.11O3, BTS11) ceramic prepared by a sol-gel method. The formation of a single perovskite structure was confirmed using the X-ray diffraction analysis. An average grain size of 18.5µm was found by the mean of the SEM micrograph with a density of 5.91 g/cm 3 .The presence of the multiphase at very near ambient temperature was proved using temperature-dependent micro-Raman measurements and differential scanning calorimetry. The BTS11 ceramic exhibits a high dielectric constant of 15460and a low dielectric loss (<0.055) with considerable temperature stability. Moreover, a high energy storage density of 122mJ/cm 3 was showed with an efficiency of 79%, and a maximum value of ECE (ΔT) of 0.86 K and finally, an electrocaloric responsivity (ΔT/ΔE) of 0.24 K.mm/kV under the external electricfield of 35 kV/cm near ambient temperature. The enhanced dielectric, ferroelectric and electrocaloric properties in BTS11 ceramic makes it a great potential candidate for its uses in solid-state cooling technology and high-energy storage applications near ambient temperature.