Electrocaloric, thermal and structural properties of Ba1−xLixTi0.975V0.025O3±δ (0 ≤ x ≤ 0.05) ceramics

Abstract

The present work reveals the electrocaloric, structural, thermal, and other physical properties of Ba1−xLixTi0.975V0.025O3±δ (0 < x ≤ 0.05) ceramics synthesized via the solid-state chemical reaction method. X-ray studies reveal the presence of BaTiO3 phase in all the samples, wherein the phase fraction of BaTiO3 decreases with increasing Li content. Besides this, the replacement of lighter weight Li-atoms in place of Ba-atoms increases porosity and consequently decreases the density of the samples. However, the molar volume increases while inter-ionic distance decreases due to the small size of Li-atoms as compared with Ba-atoms. In this series, the sample with x = 0.05 exhibited a maximum change in entropy i.e., ΔS = 0.728 JK−1 kg−1 and the largest change in temperature i.e., ΔT = 0.422 K at 90 °C with the application of a 20 kV/cm electric field. Moreover, the x = 0.05 ceramic has the largest value of specific heat i.e., 626.59 JK−1 kg−1 as discovered during DSC investigations. In the present study, Li- and V- are attributing to good sintering and Li- in place of Ba- is enhancing electrocaloric properties in BaTiO3 ceramic.