用于纤维基可穿戴传感器和电致发光器件的多功能石墨烯/聚电解质水性分散液

Versatile graphene/polyelectrolyte aqueous dispersion for fiber-basedwearable sensors and electroluminescent devices

导电分散液是构建用于可穿戴传感器、能源和柔性显示器件中导电纤维/织物的关键组成部分.尽管石墨烯具有稳定的化学性质和高电导性,但制备与纤维/织物材料兼容的石墨烯分散液仍然具有挑战性.本研究通过引入聚苯乙烯磺酸钠(PSS)分散剂,成功制备了环境友好且稳定的石墨烯水性分散液.PSS通过非共价作用改性石墨烯,使其表面带负电荷,由此产生的静电排斥促进了石墨烯的稳定分散.此外,PSS还有助于石墨烯与基底之间形成牢固的粘附.我们制备了基于石墨烯改性的纤维和纤维膜的柔性机械传感器,包括可拉伸应变传感器和压力传感器;其中,应变传感器具有100%的高拉伸性和144.6的灵敏度,也能够感知0.1%的小应变.此外,制备的柔性生理电极能够长时间记录肌电信号和心电信号.作为概念验证,制备的同轴电致发光纤维能够为潜艇模型提供照明,以完成水下复杂任务.这项工作将进一步推动先进纳米材料在可穿戴领域的应用.

Conductive dispersion is a crucial building block for obtaining conductive fibers/textiles used in wearable sen-sing,energy supply,and flexible display devices.However,despite the graphene’s stable chemical properties and high electrical conductivity,fabricating graphene dispersions compatible with fiber/textile materials remains challenging.Here,an eco-friendly and stable graphene aqueous dispersion was fabricated by introducing poly(sodium-p-styr-enesulfonate)(PSS)dispersant based on non-covalent inter-actions.Due to the modification of PSS,graphene carries negative charges,and the resulting electrostatic repulsion promotes the stable dispersion of graphene.Moreover,PSS assists graphene in forming a robust adhesion to substrates.Flexible mechanical sensors using graphene-modified fibers and fibrous membranes,including stretchable strain sensors and pressure sensors,were developed,showing high stretch-ability of up to 100%with a sensitivity of 144.6,capable of a sensing strain as small as 0.1%.Flexible electrophysiological electrodes were also fabricated to record electromyography and electrocardiograph signals for a long time.As a proof of concept,a coaxial electroluminescent fiber was demonstrated to provide illumination for a submarine model to complete complex tasks.This advancement will further propel the ad-vanced nanomaterials into wearable fields.