Zhang Ji, Baumberg Jeremy J, Kar-Narayan Sohini
Department of Materials Science & Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK.
NanoPhotonics Centre, Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK.
Soft Matter. 2024 Dec 4;20(47):9424-9433. doi: 10.1039/d4sm00886c.
Trilayer electrochemical actuators comprising an electrolyte layer sandwiched between two electrode layers have been shown to exhibit large deformations at low actuation voltages. Here we report the aerosol-jet printing (AJP) of high-aspect-ratio bending-type trilayer electrochemical microactuators comprised of Nafion as the electrolyte and poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS) as the electrode. We investigated how the thicknesses of the electrolyte and electrode layers affect the DC response of these actuators by fabricating high-aspect-ratio trilayer cantilevers with varied layer thicknesses (0.36 μm to 1.9 μm-thick electrodes, and 3.5 μm to 12 μm-thick electrolyte layers). We found that the transported charge and angular deflection are proportional to the applied voltage at steady state, and the charge-to-voltage ratio scales with the PEDOT:PSS thickness. The deflection-to-voltage ratio is found to be strongly affected by the Nafion electrolyte thickness, showing a decreasing trend, but is less affected by the PEDOT:PSS thickness in the range of dimensions fabricated. The timescales for deflection are found to be generally longer than the timescales for charge transfer and no clear trend is observed with respect to layer thicknesses. This work establishes an experimental protocol in geometry optimisation of printed electrochemical microactuators, verifies the applicability of a theoretical model, and lays the groundwork for designing and optimising more sophisticated printed electrochemical microactuation systems.
由夹在两个电极层之间的电解质层组成的三层电化学致动器已被证明在低驱动电压下会产生大变形。在此，我们报告了由Nafion作为电解质和聚（3,4 - 乙烯二氧噻吩）聚苯乙烯磺酸盐（PEDOT:PSS）作为电极组成的高纵横比弯曲型三层电化学微致动器的气溶胶喷射印刷（AJP）。我们通过制造具有不同层厚度（0.36μm至1.9μm厚的电极，以及3.5μm至12μm厚的电解质层）的高纵横比三层悬臂梁，研究了电解质层和电极层的厚度如何影响这些致动器的直流响应。我们发现，在稳态下传输电荷和角偏转与施加电压成正比，并且电荷与电压之比随PEDOT:PSS厚度而变化。发现偏转与电压之比受Nafion电解质厚度的强烈影响，呈下降趋势，但在所制造尺寸范围内受PEDOT:PSS厚度的影响较小。发现偏转的时间尺度通常比电荷转移的时间尺度长，并且未观察到关于层厚度的明显趋势。这项工作建立了印刷电化学微致动器几何优化的实验方案，验证了理论模型的适用性，并为设计和优化更复杂的印刷电化学微致动系统奠定了基础。
