Enhanced electrocaloric response and energy storage performance of Li‐substituted BaTiO ₃ ceramics

Abstract

Abstract Recently, ferroelectric and antiferroelectric ceramic materials have gained a lot of interest for the development of environment‐friendly highly‐efficient electrocaloric refrigeration and energy‐storage devices. In this work, lead‐free Ba 1− x Li x TiO 3 ceramics with x = 0, 0.01, 0.02, 0.03, 0.04, and 0.05 were synthesized by the conventional solid‐state reaction method, and the effect of Li doping on dielectric, leakage current, ferroelectric, electrocaloric, and energy storage properties of BaTiO 3 ceramics was systematically investigated. The XRD and Raman studies confirmed that the structure of Ba 1− x Li x TiO 3 remains tetragonal as for BaTiO 3 . The Li substitution shifted the phase transition ( T C ) of BaTiO 3 slightly towards the lower temperature side. Significant drop in leakage current was observed with an addition of Li content. The maximum values of the electrocaloric effect (Δ T ), electrocaloric responsivity, and coefficient of performance were found to be 1.44 K, 0.24 × 10 −6 K m/V, and 5.75, respectively, for x = 0.04 at an applied field of 60 kV/cm near the Curie temperature. The maximal value of energy storage density was found to be 0.42 J/cm 3 with an energy storage efficiency of 60% for x = 0.05. Our results suggested that lead‐free Ba 1− x Li x TiO 3 ceramic material is a promising candidate for potential applications in solid‐state refrigeration technology and high‐efficiency energy storage devices.