Detection And Sensing Application Of Hazardous Gases Ammonia And Humidity In Industrial Environment

In industrial production,changes in gas and humidity environments can have a significant impact on employee health and the safe operation of equipment.With the increase of environmental pollution,more and more harmful pollution gases have been generated that are harmful to human health.At the same time,humidity in the environment plays an important role in ensuring the stable operation of industrial equipment.Therefore,monitoring toxic gases and humidity in industrial environments is of great significance.Ammonia gas（NH₃）,as a common gas in industrial production,can have serious effects on human health even at low concentrations,such as irritating the eyes,respiratory tract,and skin,causing dizziness,nausea,and fatigue.Therefore,achieving rapid and efficient detection of NH3 is of great significance for ensuring personal safety and protecting the environment.At the same time,the quantification and control of humidity levels are very important,especially in human comfort zones and various control systems in industrial and manufacturing processes.In order to achieve an ideal surrounding environment,precise and reliable sensors must be used to monitor,detect,and control NH₃and humidity in the industrial environment under different conditions.At present,most NH₃and humidity sensors have problems such as narrow measurement range,long response time,and poor reversibility.Therefore,it is crucial to build a highly sensitive and fast data transmission integrated system for gas humidity detection.This article combines nanomaterials with interdigital feedback sensing components to design four humidity/ammonia sensors.They are resistive ammonia sensors based on cerium oxide（Ce O₂）material,resistive ammonia sensors based on copper ferrite（Cu Fe₂O₄）material,capacitive humidity sensors based on Ce O₂material,and resistive humidity sensors based on graphite phase carbon nitride（g-C₃N₄）material.The composition,morphology,and structure of the three compounds were analyzed by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,and X-ray photoelectron spectroscopy（XPS）.Compared to ammonia sensors based on Cu Fe₂O₄material,ammonia sensors based on Ce O₂material have unique advantages in response/recovery time（14 s/22 s@50 ppb NH₃）and minimum detection limit（25 ppb）.At the same time,it also has good stability（over 60 days）.The ammonia sensor based on Cu Fe₂O₄material performs better in terms of detection range（1-50 ppm）and sensitivity（81.93%@50 ppm NH₃）.Its response time and recovery time are 84seconds and 54 seconds respectively.In response to the problems of high energy consumption,weak detection signal,and inconvenient data transmission in ammonia gas sensors,an integrated detection system integrating high sensitivity gas sensors and detection transmission has been constructed,which can be used for the detection and alarm of NH₃in industrial pollution gases.The two types of ammonia gas sensors developed have their own unique performance advantages,which can complement each other and meet different NH₃monitoring environments.For capacitive Ce O₂humidity sensors,the response value of the sensor reaches 6573 when the relative humidity（RH）increases from 0%to 97%.Compared with traditional humidity sensors,Ce O₂nanosensors have significant advantages in sensitivity（959.5 p F/%RH）,response speed,stability,and recovery time.Meanwhile,the resistive humidity sensor based on g-C₃N₄nanosheet thin film has advantages such as high sensitivity（6457548.8Ω/%RH）,strong anti-interference ability,and fast response/recovery time（0.3/11 s）.The developed capacitive and resistive humidity sensors can meet the requirements of various electrical acquisition devices and complement each other’s advantages for humidity sensing applications in multiple scenarios.An integrated system based on NFC detection and transmission has been designed for capacitive sensor components.While exploring the field of micro and nano sensing,electronic information technology has been used to solve the problem of sensing data transmission.