Nanoscale domain patterns and a concept for an energy harvester
Nanoscale domain patterns and a concept for an energy harvester
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DOI：
10.1088/0964-1726/25/10/104001
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发表时间：
2016-09
影响因子：
4.1
通讯作者：
A. R. Balakrishna;J. Huber
中科院分区：
文献类型：
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作者：
A. R. Balakrishna;J. Huber
目前的工作采用相场模型来测试纳米级周期性畴图案的稳定性，并探索一种图案在能量收集器设备中的应用。首先，在无应力和无电场的条件下，测试了几种具有面内极化的周期性畴图的稳定性。结果发现，简单的域模式与条纹状的功能是稳定的，而更复杂的域配置的模式通常是不稳定的纳米尺度。在识别出具有合适性质的稳定域图案后，探索了薄膜能量收集器装置的概念设计。收割机被建模为一个铁电薄膜绑定到一个基板。在初始状态下，模拟了顶部电极上具有零净电荷的周期性条纹畴图案。在弯曲衬底时，在膜中引起机械应变，导致极化域经历铁电切换，从而产生电能。结果展示了概念性能量采集器的工作循环，该能量采集器在kHz频率下工作，例如来自环境中的振动，可以产生约40 W m−2的面积功率密度。
The current work employs a phase-field model to test the stability of nanoscale periodic domain patterns, and to explore the application of one pattern in an energy harvester device. At first, the stability of several periodic domain patterns with in-plane polarizations is tested under stress-free and electric field-free conditions. It is found that simple domain patterns with stripe-like features are stable, while patterns with more complex domain configurations are typically unstable at the nanoscale. Upon identifying a stable domain pattern with suitable properties, a conceptual design of a thin film energy harvester device is explored. The harvester is modeled as a thin ferroelectric film bound to a substrate. In the initial state a periodic stripe domain pattern with zero net charge on the top electrode is modeled. On bending the substrate, a mechanical strain is induced in the film, causing polarized domains to undergo ferroelectric switching and thus generate electrical energy. The results demonstrate the working cycle of a conceptual energy harvester which, on operating at kHz frequencies, such as from vibrations in the environment, could produce an area power density of about 40 W m−2.