Improved electrocaloric effect and working temperature span in BaTiO3-based ferroelectric ceramics via texture engineering†

The electrocaloric effect (ECE) is promising in solid-state refrigeration applications. However, achieving this has been facing long-term challenges in terms of high adiabatic temperature change (ΔT) and wide working temperature span (T_span). Herein, we demonstrated that texture engineering could effectively address these problems, based on a systematic study of the electrocaloric (EC) response of the random, 〈001〉 and 〈111〉 textured BaHf_0.11Ti_0.89O₃ ceramics with the rhombohedral phase in majority. Particularly, the 〈111〉 textured ceramics simultaneously exhibited the highest ΔT (1.48 K) and largest T_span (65 °C) under an electric field of 50 kV cm⁻¹, which were respectively 1.3 and 1.7 times those of the random one. In essence, the outstanding EC responses originated from the polarization rotation and increasing relaxation behavior after texture engineering. This study provides an effective approach to promote the EC performance of BaTiO₃-based ceramics and can also be expanded to a variety of dielectric materials.