Fabrication And Properties Of Flexible Pressure Sensors Based On Conductive Fabric

Electronic textiles?E-textiles?have attracted a great deal of attention in next-generation wearable electronics due to their facile integration into clothes.Various electronic elements such as physical or biological sensors,energy harvesting devices,field-effect transistors and antennas have bonded into E-textiles.In particular,wearable pressure sensor with force-sensitive properties,which can mimic and surpass the function of human skin by transducing external tiny stimuli such as touching,shear and mechanical vibration into electrical signals,has been widely explored for diagnostics,monitoring patients,human motion detection,etc.To meet the needs of wearable electronics,pressure sensors are required to be ultra-sensitive,comfortable,breathable,washable,flexible and robust.However,most of the traditional wearable sensors are fabricated using airproof and non-renewable elastic substrates,which are unfavorable to the skin's breathing for large-area application.Those disadvantages will greatly limit its prospects in the application of E-skin.In contrast,textile substrates are skin-friendly,renewable and offer enormous opportunities to deploy sensors and other devices,which are promising for E-textiles.Here,we demonstrate a novel structure of all-textile-based pressure sensors and large-area sensor arrays,and two kinds of resistive flexible pressure sensor were fabricated.The main research contents are as the follows:?1?Design and preparation of textile-based pressure sensors based on AgNWs-coated cotton fabric.The resistive textile sensor unit is composed of a bottom interdigitated textile electrode screen-printed using silver paste and a top ridge of AgNWs-coated cotton fabric.The pressure sensors maintained ultra-sensitivity of 2.46?10⁴-5.65?10⁵ kPa^-1 in a wide pressure range?<30 kPa?,which is among the best results for wearable pressure sensors.Moreover,the textile sensor achieved fast response time,low detection limit,and high stability.These remarkable detective performances show our sensors could detect varied tiny stimulations and facilely integrate with other functional devices.?2?Design and preparation of textile-based pressure sensors based on polyaniline?PANI?wrapped nonwoven fabric.The PANI were in-situ synthesized on the fibers surface and the textile electrodes are screen-printed.Nonwoven fabric has a random fiber network microstructure,which endows the rough surface with Gaussian random distribution surface?GRDS?.Own to the GRDS of the piezoresistive materials,our pressure sensors maintained ultra-sensitivity of 46.48 kPa^-1 in a wide linearity range?<4.5 kPa?,which is among the best results for wearable pressure sensors.Moreover,the textile sensor could achieve fast response/relaxation time,low detection limit,and high stability.These excellent detective performances show our sensors could detect wrist pulse,acoustic waves and respiration signals.?3?Textile-based pressure sensors applied in human-computer interactive systems.Large-area sensor arrays could be facilely printed on clothes and applied in human-computer interactive systems.Such pressure sensor arrays and a fabrication process should be promising in the field of interactive wearable electronics,smart fabrics and robotic systems.In summary,high-performance flexible sensor arrays could be fabricated and applied in physiological signals monitoring and human-computer interactive systems,such pressure sensors should be promising in flexible electronics.