柔性可穿戴湿度传感器的研究进展

Research progress of flexible wearable humidity sensors for application

柔性可穿戴智能设备如智能手表、手环等在日常生活中发挥着重要作用,尤其是在医疗保健和运动监测等方面。传统刚性湿度传感器件存在柔韧性差、体积庞大、质量大以及需要传统电池供电等缺陷,无法与人体力学相匹配,因而不能检测皮肤表明湿度变化,柔性可穿戴乃至可自供电的新型湿度传感器是传统湿度传感器的有效替代品。柔性可穿戴湿度传感器的吸湿主要依靠水分子的物理、化学吸附机制。湿敏材料主要有有机高聚物及无机低分子物。柔性可穿戴湿度传感器可分为电阻式、电容式、电压式湿度传感器。电阻式湿度传感器的电阻随环境湿度、交流频率的增加而逐渐减小,且灵敏度降低,但其具有良好的可重复使用性;电容式湿度传感器的电容随着湿度的增加而增大,响应恢复性和耐久性好;电压式湿度传感器既可以作为电压传感器使用,又可利用湿气发电,其电压随着湿度的增加而减小,响应恢复时间短,可循环使用性强。3种柔性湿度传感器在人体健康监测和环境湿度检测调控等方面具有重要作用。

Flexible wearable smart devices such as smart watches and bracelets play a crucial role in daily life,particularly in the fields of healthcare and sports monitoring.Traditional rigid humidity sensing devices have several limitations,including poor flexibility,bulky size,heavy mass weight,and the need for traditional battery power supply.These shortcomings prevent them from accurately detecting changes in skin surface humidity and adapting to the mechanics of the human body.Therefore,there is a growing need for novel humidity sensors that are flexible,wearable,and possibly self-powered to replace traditional sensors.The moisture absorption of flexible wearable humidity sensors primarily relies on the physical and chemical adsorption mechanisms of water molecules.Moisture-sensitive materials include organic polymers,synthetic polymers,and inorganic low-molecular substances.Flexible wearable humidity sensors can be categorized into resistive,capacitive,and voltage types.The resistance of resistive humidity sensors gradually decreases,and the sensitivity decreases as the environmental humidity and alternating current frequency increase,but they exhibit good reusability.The capacitance of the capacitive humidity sensors increases with the increase of humidity,their response recovery and durability are good.Voltage humidity sensors can be utilized for voltage sensing monitoring and moisture power generation applications,with the voltage decreasing as humidity increasing,and exhibiting fast response recovery and strong excellent recyclability.These three types of flexible humidity sensors play a significant role in human health monitoring and environmental humidity detection monitoring and regulation.