Lin Yezhan, Bao Yizheng, Yan Shiguang, Chen Bowen, Zou Kai, Nie Hengchang, Wang Genshui
Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, People's Republic of China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, 19 Yuquan Road, Shijinshan District, Beijing 100049, P. R. China.
ACS Appl Mater Interfaces. 2022 Oct 26. doi: 10.1021/acsami.2c12388.
Thermal conductivity dominates in a heat transfer medium, and a field modulated would facilitate delicate control in thermal management technology, yet it is hardly realized in a single solid material unless with changing temperature. Herein, in BaTiO ceramic, a modulated was discovered by adjusting ferroelectric polarization , which was a conventional strategy in ferroelectric functional materials. Four different states (P1, P2, P3, P4) were obtained by controlling poling time and field strength, showing that leaped from 2.704 ± 0.054 to 3.201 ± 0.070 W (m K) with increased . Moreover, the strong correlation between and was also verified by the thermal depolarization measurement from room temperature to Curie temperature. The underlying origin of modulated was attributed to the internal bias field, which is born in the oriented ferroelectric domains, tightening special phonon modes in BaTiO ceramics. Raman spectrum, - loops, first-order reversible curve, XRD analysis, and PFM measurement were then employed to clarify how ferroelectric polarization structurally influences phonon transport and subsequent thermal conductivity. This work will pave a brand-new research route for conventional ferroelectric ceramic, also potentiating the idea of the electric field-controlled component and active solid heat-transport device in the future.
热导率在传热介质中起主导作用，场调制有助于热管理技术中的精确控制，但在单一固体材料中很难实现，除非温度发生变化。在此，在钛酸钡（BaTiO）陶瓷中，通过调节铁电极化发现了一种调制现象，这是铁电功能材料中的一种传统策略。通过控制极化时间和场强获得了四种不同状态（P1、P2、P3、P4），结果表明，随着极化强度增加，热导率从2.704±0.054跃升至3.201±0.070W/（m·K）。此外，通过从室温到居里温度的热退极化测量，也验证了热导率与极化强度之间的强相关性。热导率调制的潜在起源归因于内偏场，它产生于取向的铁电畴中，收紧了钛酸钡陶瓷中的特定声子模式。随后采用拉曼光谱、电滞回线、一阶可逆曲线、X射线衍射分析和压电响应力显微镜测量，以阐明铁电极化如何在结构上影响声子输运以及随后的热导率。这项工作将为传统铁电陶瓷开辟一条全新的研究途径，也增强了未来电场控制热导率组件和有源固体热传输器件的概念。
