Giant intrinsic electrocaloric effect in ferroelectrics by local structural engineering

作者：Bo Wu, Hong Tao, Kui Chen, Zhipeng Xing, Yanqi Wu, Hao‐Cheng Thong, Lin Zhao, Chunlin Zhao, Ze Xu, Yixuan Liu, Fang‐Zhou Yao, Tianhang Zhou, Jian Ma, Yan Wei, Ke Wang, Shujun Zhang · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-61860-5 · 被引用次数：11 · 研究领域：Ferroelectric and Piezoelectric Materials、Dielectric materials and actuators、Multiferroics and related materials

The electrocaloric effect of ferroelectrics holds great promise for solid-state cooling, potentially replacing traditional vapor-compression refrigeration systems. However, achieving adequate electrocaloric cooling capacity at room temperature remains a formidable challenge due to the need for a high intrinsic electrocaloric effect. While barium titanate ceramic exhibits a pronounced electrocaloric effect near its Curie temperature, typical chemical modifications to enhance electrocaloric properties at room temperature often reduce this intrinsic electrocaloric effect. Herein, a structural design is introduced for barium titanate-based ceramics by incorporating isovalent cations. This leads to a well-ordered local structure that decreases the Curie temperature to room temperature while preserving a sharp phase transition, enabling a large dielectric constant and tunable polarization. This design achieves a remarkable electrocaloric strength of ~1.0 K·mm/kV, surpassing previous reports. Atomic-resolution structural analyses reveal that the presence of multiscale nanodomains (from ~10 nm to >100 nm), and the dipole polarization distribution with gradual dipole rotation enable rapid phase transition and facile polarization rotation, accounting for the giant electrocaloric response. This work provides a strategy for achieving a strong intrinsic electrocaloric effect in ferroelectrics near room temperature and offers key insights into the microstructure landscapes driving this enh...