Study On Humidity Sensor Based On Hydrophilized Candle Soot Nanoparticle Layers

The change of humidity is closely related to human life.The monitoring of humidity is of great significance in the fields of meteorology,health care,agricultural production and safety engineering.In this paper,a new kind of humidity sensitive material was developed by using oxygen plasma technology combined with candle ash nanoparticle layer.The humidity sensor is designed in this paper by using oxygen plasma treatment is full after the changes of chemical groups on the surface candle ashes nanoparticles and candle ashes of nano-particle porous layer itself characteristics to achieve the humidity testing,and through the further experiments to explore the humidity sensor monitoring the breath frequency,skin moisture test and the prospect for application of non-contact switch direction,prove that it is expected to wearable devices,personality,medical and other fields has important research value.The main research contents of this paper are as follows:(1)preparation of hydrophilic candle ash nanoparticle layer and study on its moisture sensitivity mechanism.Hydrophilic candle ash nanoparticle layer was prepared by using oxygen plasma technology and microelectronic process,and the morphology,surface groups,microscopic size,surface wettability and other parameters of candle ash nanoparticle layer were tested.(2)preparation and testing of humidity sensor based on hydrophilic candle ash nanoparticle layer.According to the characteristics of moisture sensitivity of the nanoparticle layer of candle ash and the change of its physical and chemical properties after absorbing water molecules,the resistive and QCM humidity sensors based on the hydrophilic candle ash nanoparticle layer were designed respectively.Finally,a humidity sensor testing platform was built to test the sensitivity and stability of the humidity sensor,and the process parameters affecting the performance of the humidity sensor were analyzed and optimized.(3)application exploration of humidity sensor based on hydrophilic candle ash nanoparticle layer.Based on the characteristics of wet-sensitive performance of resistance humidity sensor of hydrophilic candle ash nanoparticle layer,its application prospect in wearable devices,flexible electronics and personalized medical treatment was explored.Completed its preliminary application in respiratory frequency,skin moisture testing and other direction of the experiment,and through the analysis of experimental results,confirmed the humidity sensor can pass the test humidity fluctuations in response the change of respiratory frequency,and reaction of motion,can also distinguish the skin after coated with different cosmetics moisturizing length,for the future laid the foundation for the further application in various fields.In summary,a new type of humidity sensitive material based on hydrophilic candle ash nanoparticle layer was developed in this paper.By making full use of its humidity sensitive characteristics,resistance type and QCM type humidity sensors based on hydrophilic candle ash nanoparticle layer were designed and prepared.On this basis,the application prospect of the humidity sensor in the fields of health electronics and personalized medical treatment is explored.In addition,the preparation process of the humidity sensor is simple and convenient,which is expected to realize the batch preparation of low-cost and highly sensitive humidity sensor.