Poisson-Nernst-Planck framework for modelling ionic strain and temperature sensors.
Poisson-Nernst-Planck framework for modelling ionic strain and temperature sensors.
复制标题
用于模拟离子应变和温度传感器的 Poisson-Nernst-Planck 框架。
DOI：
10.1039/d2tb02819k
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Bettinger,ChristopherJ
中科院分区：
文献类型：
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作者：
Balakrishnan,Gaurav;Song,Jiwoo;Khair,AdityaS;Bettinger,ChristopherJ
离子导电水凝胶作为生物电子设备的传感和结构材料越来越受到关注。具有较大机械顺应性和易于处理的离子电导率的水凝胶是一种引人注目的材料，它可以感知生理状态，并可能调节可兴奋组织的刺激，因为组织-材料界面上的机电特性具有一致性。然而，将离子水凝胶与传统的基于直流电压的电路连接带来了一些技术挑战，包括电极分层、电化学反应和漂移接触阻抗。利用交流电压探测离子弛豫动力学已被证明是应变和温度传感的可行替代方案。在这项工作中，我们提出了泊松-能斯特-普朗克理论框架，用于模拟受不同应变和温度影响的导体内交变场下的离子传输。使用模拟阻抗谱，我们对所施加电压扰动的频率与灵敏度之间的关系有了重要的了解。最后，我们进行了初步的实验表征，以证明所提出的理论的适用性。我们相信这项工作提供了一个有用的视角，适用于生物医学和软机器人应用的各种基于离子水凝胶的传感器的设计。
Ionically conductive hydrogels are gaining traction as sensing and structural materials for use bioelectronic devices. Hydrogels that feature large mechanical compliances and tractable ionic conductivities are compelling materials that can sense physiological states and potentially modulate the stimulation of excitable tissue because of the congruence in electro-mechanical properties across the tissue-material interface. However, interfacing ionic hydrogels with conventional DC voltage-based circuits poses several technical challenges including electrode delamination, electrochemical reaction, and drifting contact impedance. Utilizing alternating voltages to probe ion-relaxation dynamics has been shown to be a viable alternative for strain and temperature sensing. In this work, we present a Poisson–Nernst–Planck theoretical framework to model ion transport under alternating fields within conductors subject to varying strains and temperatures. Using simulated impedance spectra, we develop key insights about the relationship between frequency of the applied voltage perturbation and sensitivity. Lastly, we perform preliminary experimental characterization to demonstrate the applicability of the proposed theory. We believe this work provides a useful perspective that is applicable to the design of a variety of ionic hydrogel-based sensors for biomedical and soft robotic applications.