Direct Detection of Local Electric Polarization in the Interfacial Region in Ferroelectric Polymer Nanocomposites
Direct Detection of Local Electric Polarization in the Interfacial Region in Ferroelectric Polymer Nanocomposites
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DOI：
10.1002/adma.201807722
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发表时间：
2019-05-01
影响因子：
29.4
通讯作者：
He, Jinliang
中科院分区：
文献类型：
--
作者：
Peng, Simin;Yang, Xiao;He, Jinliang
铁电聚合物纳米复合材料由于其优异的电极化性能和易于制备而被广泛应用于电容储能、电热制冷和机械能收集等领域。一般认为铁电纳米复合材料的异常性能源于聚合物基体与嵌入纳米颗粒之间的界面区域。然而，在界面区域的独特的局部电极化属性的直接证据是尚未访问。本文报道了一种改进的Kelvin探针力显微镜（KPFM）方法，该方法具有纳米级的空间分辨率，可用于直接检测铁电纳米复合材料中基体/颗粒界面的局部极化特性。典型的铁电纳米复合材料使用本方法进行了研究。定量地探讨了在外加电场作用下，基体/颗粒界面区域的电极化程度高于聚合物基体。考虑到改进的KPFM测量的增强的局部电极化，铁电聚合物纳米复合材料的介电性能与本体实验表征相匹配，表明所建立的方法是可靠的。可以预见，本方法，开辟了新的可能性，在了解基体/颗粒界面区域，可能有助于明智的设计和工程的高性能铁电聚合物纳米复合材料。
Ferroelectric polymer nanocomposites are widely used in capacitive energy storage, electrocaloric refrigeration, and mechanical energy harvesting due to their exceptional electric polarization property and ease of fabrication. It is generally considered that the abnormal performance of ferroelectric nanocomposites stems from the interfacial region between the polymer matrix and embedded nanoparticles. However, direct evidence of the distinct local electric polarization property at the interfacial region is not yet accessible. Herein, a modified Kelvin probe force microscopy (KPFM) method with nanoscale spatial resolution is reported for direct detection of local polarization property at the matrix/particle interface in ferroelectric nanocomposites. Typical ferroelectric nanocomposites are studied using the present method. It is quantitatively probed that the electric polarization at matrix/particle interfacial region is higher than the polymer matrix under applied electric fields. Taking into account the enhanced local electric polarization gauged by the modified KPFM, the dielectric property of ferroelectric polymer nanocomposites matches with bulk experimental characterizations, indicating that the established method is reliable. It is anticipated that the present method, opening up new possibilities in understanding the matrix/particle interfacial region, may help with judicious design and engineering of high-performance ferroelectric polymer nanocomposites.