Hierarchically Plied Mechano-Electrochemical Energy Harvesting Using a Scalable Kinematic Sensing Textile Woven from a Graphene-Coated Commercial Cotton Yarn

Abstract

Wearable sensing systems are suitable for monitoring human motion. To realize a cost-effective and self-powered strain-sensing fiber, we developed a mechano-electrochemical harvesting yarn and textile using hierarchically arranged plied yarns composed of meter-long graphene-coated cotton yarns. Such a fiber relies on the principle of electrochemical capacity change to convert mechanical energy to electric energy. Further, this harvester can be used as a self-powered strain sensor because its output depends on mechanical stimuli. Additionally, the yarn can be woven into a kinematic sensing textile that measures the strength and direction of the applied force. The textile-type harvester can successfully detect various human movements such as pressing, bending, and stretching. The proposed sensing fiber will pave the way for the development of advanced wearable systems for ubiquitous healthcare in the future.

Ta4C3 Nanosheet/Melamine Sponges with High Sensitivity and Long-Term Stability for Wearable Piezoresistive Sensors

“…To enhance the sensitivity of sensors using the melamine sponge, it is necessary to incorporate conductive fillers into the sponge to create a three-dimensional (3D) conductive network . Various nanomaterials, such as carbon nanotubes (CNTs), , carbon nanofiber, graphene, , metal nanoparticles, and silver nanowires, have been utilized as active conductive materials for flexible sensor fabrication. Sensors based on a melamine matrix with these conductive fillers have demonstrated remarkable sensing performance.…”

Outstanding Synergy of Sensitivity and Linear Range Enabled by Multigradient Architectures

“…Flexible pressure sensors that transduce the external forces into electrical signals endow intelligent robotics, artificial prosthetics, wearable electronics, and human-machine interfaces with mechanosensory functions. − Mechanical inputs from the environment are converted to real-time electrical signals by distinct types of pressure sensors, including capacitive, − piezoelectric, − triboelectric, − and piezoresistive sensors. − A piezoresistive sensor that transduces pressure stimuli to resistance/current signals presents the advantages of simple structures and manufacturing processes, easy signal collection and readout mechanisms, and cost-effectiveness in fabrication. To meet the application requirements in complex scenarios, the pressure sensor often requires high sensitivity, excellent linearity over a broad pressure range, and high pressure resolution. ,,− Much effort has been devoted to engineering the active materials with surface micro/nanostructures, such as dome/pyramid/cone/pillar arrays, for improving the sensitivity and simultaneously broadening the pressure range. − Although encouraging progress has been made, the pressure sensors often possess varying sensitivity values within different pressure ranges due to the structural stiffening of such microstructures and corresponding signal attenuation with increasing pressure.…”