Preparation And Performance Study Of Perovskite Humidity Sensor Based On Electric Atomization Technology

In the information age,sensing technology has become increasingly widely used.As a unit for monitoring and collecting environmental humidity information,humidity sensors are widely used in fields such as human respiration,industrial production,and medical devices.With the continuous deepening of social demand,there is a higher demand for improving the response speed and sensitivity of humidity sensors.In recent years,humidity sensors based on new humidity sensitive materials,perovskite,have entered people’s vision.Although its high sensitivity and fast response characteristics are highly attractive,the impact of its molding process on performance is also challenging.This article utilizes electro atomization deposition technology and adopts a two-step atomization method to react CH3NH3I(MAI)and PbI2 precursors to form a perovskite humidity sensitive layer.By adjusting process parameters to control the surface morphology of perovskite thin films,a higher quality perovskite humidity sensitive thin film was prepared compared to traditional spin coating processes.The tasks completed in sequence include:(1)Analysis of the Theory of Electrostatic Atomization.Considering the comprehensive force acting on the precursor droplets,the mechanism of droplet fragmentation and atomization was studied.The selection of precursor droplet atomization modes that are conducive to uniform film preparation was theoreti0cally carried out,and the theoretical conditions for obtaining stable conical jets were studied and analyzed.Based on the research and analysis of electrostatic atomization theory,a platform for electrostatic atomization technology has been established.(2)Preparation of porous needle branched PbI2 thin films.By adjusting the composition and ratio of PbI2 precursor solvent,as well as improving the structure of the printing needle,a longterm stable atomization precursor liquid mist field was obtained.On this basis,the influence of electro atomization process parameters on the stability of the precursor liquid mist field and the surface morphology of PbI2 thin films was studied,and the process parameters were optimized to prepare porous needle branched PbI2 thin films.(3)Preparation of rough porous perovskite humidity sensitive thin films.Explored the influence of MAI precursor working distance on the surface morphology and composition of perovskite thin films.By replacing the needle material,stable atomization was achieved at low working distance,and PbI2 free perovskite thin films were prepared;Then,by exploring the relationship between the flow rate of MAI precursor and the surface morphology of perovskite films,rough and porous perovskite film morphology was prepared.(4)Performance testing of perovskite humidity sensors.A humidity testing platform was built to test the performance of perovskite humidity sensors,and a comparative analysis was conducted on devices prepared by electric atomization and spin coating processes.The results indicate that the devices prepared using the electro atomization process have higher sensitivity and responsiveness,indicating that the performance of the devices prepared using the electro atomization process is significantly improved compared to the spin coating process.