Fundamental Limits to the Electrochemical Impedance Stability of Dielectric Elastomers in Bioelectronics
Fundamental Limits to the Electrochemical Impedance Stability of Dielectric Elastomers in Bioelectronics
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DOI：
10.1021/acs.nanolett.9b03705
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发表时间：
2020-01-01
期刊：
影响因子：
10.8
通讯作者：
Liu, Jia
中科院分区：
文献类型：
--
作者：
Le Floch, Paul;Molinari, Nicola;Liu, Jia
将弹性体结合到生物电子学中，减少了电子和生物系统之间的机械不匹配，可能会长期改善电子-组织界面。然而，弹性体在生理条件下的长期稳定性尚未得到系统的研究。在这里，利用电化学阻抗谱，我们发现介电弹性体的电化学阻抗在生理环境中随着时间的推移而退化。实验和计算结果都表明，这种现象是由于离子从生理溶液中扩散到弹性体中。它们的电导率增加了6个数量级，达到10(-8)S/m。当钝化导体也由本质上可拉伸的材料组成时，可以检测到更高的泄漏电流。尺度分析表明，由可拉伸材料制成的互连的电气性能存在基本限制。
Incorporation of elastomers into bioelectronics that reduces the mechanical mismatch between electronics and biological systems could potentially improve the long-term electronics-tissue interface. However, the chronic stability of elastomers in physiological conditions has not been systematically studied. Here, using electrochemical impedance spectrum we find that the electrochemical impedance of dielectric elastomers degrades over time in physiological environments. Both experimental and computational results reveal that this phenomenon is due to the diffusion of ions from the physiological solution into elastomers over time. Their conductivity increases by 6 orders of magnitude up to 10(-8) S/m. When the passivated conductors are also composed of intrinsically stretchable materials, higher leakage currents can be detected. Scaling analyses suggest fundamental limitations to the electrical performances of interconnects made of stretchable materials.