Research On Humidity Sensor Based On Zwitterionic Polymer

The environment in which people live is closely related to humidity,which is an important parameter to measure the degree of atmospheric dryness.The detection and control of humidity is crucial for various important fields including industries,agriculture,climatology,medical services,food,new material development and daily life.In recent years,with the development of smart materials,new types of humidity sensors have been applied to all aspects of people's daily lives,including smart homes and human skin detection.Therefore,people have also increased their requirements for humidity sensors,and on the basis of high sensitivity and accuracy,they have further explored the intelligence and miniaturization of humidity sensors.As far as the materials for low-cost humidity sensors are concerned,carbon-based materials become the researchers'first choice due to their extraordinary chemical and physical properties.In this paper,for the first time,we fabricate capacitive humidity sensors based on zwitterion.The zwitterion-based humidity sensors exhibited high sensitivity,fast response,small hysteresis,and more important,wide working range of relative humidity(RH).The sensors showed>10~2 times increase in sensing signal over 40%?90%RH range at 20 Hz.After experiencing the influence of external conditions such as immersion water and salt solution,high and low temperature(-20?-60?)and heavy pressure,the sensor signal is almost unchanged,which shows great durability and strong resistance to environmental interference.Flexible zwitterion-based humidity sensors were also fabricated,and displayed excellent sensing properties with long-time stability,endowing it with multifunctional applications.Our sensors can realize distinction on nuance for humidity and exhibited outstanding non-contact skin humidity sensing properties.The contrast humidity sensing experiment compared to the existing commercial humidity sensor further demonstrated the higher and faster response of zwitterion-based sensors.In addition,Due to its own porous structure,the sensor presents excellent gas and sweat permeability,it precisely detects the humidity level of an object for a long time.