Zheng Lijing, Zhu Miaomiao, Wu Baohu, Li Zhaoling, Sun Shengtong, Wu Peiyi
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Chemistry, Chemical Engineering and Biotechnology & Center for Advanced Low-dimension Materials, Donghua University, Shanghai 201620, China.
College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
Sci Adv. 2021 May 28;7(22). doi: 10.1126/sciadv.abg4041. Print 2021 May.
Highly conductive and stretchy fibers are crucial components for smart fabrics and wearable electronics. However, most of the existing fiber conductors are strain sensitive with deteriorated conductance upon stretching, and thus, a compromised strategy via introducing merely geometric distortion of conductive path is often used for stable conductance. Here, we report a coaxial wet-spinning process for continuously fabricating intrinsically stretchable, highly conductive yet conductance-stable, liquid metal sheath-core microfibers. The microfiber can be stretched up to 1170%, and upon fully activating the conductive path, a very high conductivity of 4.35 × 10 S/m and resistance change of only 4% at 200% strain are realized, arising from both stretch-induced channel opening and stretching out of tortuous serpentine conductive path of the percolating liquid metal network. Moreover, the microfibers can be easily woven into an everyday glove or fabric, acting as excellent joule heaters, electrothermochromic displays, and self-powered wearable sensors to monitor human activities.
高导电性和可拉伸纤维是智能织物和可穿戴电子产品的关键组件。然而，现有的大多数纤维导体对应变敏感，拉伸时电导会恶化，因此，通常采用仅引入导电路径几何变形的折衷策略来实现稳定的电导。在此，我们报道了一种同轴湿法纺丝工艺，用于连续制造本质上可拉伸、高导电性且电导稳定的液态金属皮芯微纤维。该微纤维可拉伸至1170%，在完全激活导电路径后，实现了4.35×10 S/m的极高电导率，在200%应变下电阻变化仅为4%，这源于拉伸诱导的通道开放以及渗流液态金属网络曲折蜿蜒导电路径的伸展。此外，这些微纤维可以轻松编织成日常手套或织物，用作出色的焦耳加热器、电热变色显示器和自供电可穿戴传感器，以监测人类活动。
