液态金属

Abstract(#br)In this study, we present a dimension-controllable 3D biomedical microelectrode based on low melting point metals (Bi/In/Sn/Zn alloy) applied using the phase transition method. We have established a process, in which the liquid metal is pumped through a syringe needle of the dispensing system to form a needle shape after cooling at room temperature. PDMS (polydimethylsiloxane) was chosen as the substrate of the electrode as it is amenable to micro-molding and has excellent flexibility.

Abstract(#br)An all-soft, highly stretchable liquid metal (LM) conductor with high electrical conductivity, excellent electrical conductivity stability under various mechanical deformations and good mechanical properties was achieved. The stretchable conductor was prepared by infiltrating Gallium-indium-tin (GIT) LM into porous polyurethane sponge (PUS) with large porosity and small pores using a vacuumizing method followed by encapsulation with Polydimethylsiloxane (PDMS) to prevent the leakage of GIT-LM and to improve the mechanical properties.

Abstract(#br)Hypothesis(#br)Controlling the wetting behaviour of gallium-based liquid metal is highly desired for soft electronics applications. Currently, achieving durable and patternable liquid-metal-repellent surfaces by a simple and flexible method is challenging. The femtosecond laser has a remarkable ability to modify the morphology and wettability of a solid surface.

导电纺织品( CTs )是很有前途的电磁干扰( EMI )屏蔽材料。尽管如此，有限的可伸缩性和较差的可靠性限制了它们在可伸缩电子器件中的潜在应用，因为导电网络是刚性的。本文通过设计可变形液态金属( LM )涂层和聚二甲基硅氧烷( PDMS )保护层，研制了一种高伸展性、高可靠性的有效EMI屏蔽CT。在厚度仅为0.35 mm时，PDMS-LM /纺织品表现出优异的EMI屏蔽效能( EMI SE )，在应变为30 %和50 %时，EMI SE分别保持66.0和52.4 dB。对应的EMI SEs在5000次拉伸-释放循环后分别保留91.7 %和80.3 %。优越而持久的EMI SE应归功于导电LM网络良好的连通性和良好的变形能力。此外，LM涂层对纺织品基体有较强的牢度，经10 min超声处理和100次剥离循环后，由于PDMS层的保护作用，EMI SE没有明显下降。本文的工作为开发高可伸缩性CTs，特别是在高可伸缩性电子器件领域的高级EMI屏蔽应用提供了新的途径。

本研究通过液相金属( LMs )的掺入，制备了高性能、可调谐微波屏蔽的多壁碳纳米管填充聚二甲基硅氧烷( CNT / PDMS )复合材料。第二，将LM和固化剂以手动搅拌的方式加入到CNT / PDMS混合物中，得到均匀的CNT / LM / PDMS混合物。然后固化，得到最终的CNT / LM / PDMS复合材料。复合材料的高性能微波屏蔽能力归因于纳米CNTs与微米LM粒子之间的协同作用。具体而言，含有2.5   vol . % LM和3.0   vol . % CNT颗粒的复合材料实现了42.6   d B的微波屏蔽效能。此外，复合材料具有较高的吸收损耗和较低的反射损耗，可有效降低二次微波污染。更为重要的是，含LMs的复合材料的微波屏蔽性能可以通过压缩来调节，这是因为LM粒子的聚集和裂纹的形成。

软电子系统需要可伸缩、可打印的导体，用于软机器人、可穿戴技术和人机接口的应用。镓基室温液态金属( LMs )已成为很有前途的候选材料，最近液态金属嵌入弹性体( LMEEs )表现出了良好的性能，如应变时电导率稳定、循环耐久性和可图形化等。在此，我们提出了一种乙醇/聚二甲基硅氧烷/液态金属( EtOH / PDMS / LM )双乳液墨水，该墨水能够快速、可伸缩地打印出电导率高( 7.7×105S m-1 )、应变时电阻变化小、循环性能一致(超过1万次循环)的LM导体。载体溶剂EtOH因粘度低而被用来将油墨打印到有机硅基底上。PDMS驻留在EtOH / LM界面上，在沉积和EtOH蒸发时固化，从而将LM颗粒粘结在彼此和有机硅基底上。印制的PDMS-LM复合材料随后可被直接激光写入激活，形成高分辨率的导电通路。我们通过为可拉伸的电子电路创建错综复杂的电气互连来论证双乳液油墨的效用。本工作将激光辅助制造的速度、一致性和精度与PDMS-LM复合材料的印刷适性、高导电性、应变不敏感性和机械稳健性相结合，解锁高产率、高通量、高密度可拉伸电子。