Based On The Study Of The Stability Of Lead-free Perovskite Humidity Detectors

Since ancient times,humidity has always been an environmental parameter that people are concerned about,mainly because humidity has an important impact on the growth and life of animals and plants,the development of agriculture and animal husbandry,the storage and transportation of goods and food,the launch of rockets,and the survival and health of human beings.As an important tool for people to perceive humidity information in the environment,humidity detectors are convenient for people to perform real-time monitoring and precise control of specific environments.For this reason,domestic and foreign scholars have studied many new types of humidity-sensitive materials in order to obtain high-performance humidity detectors.However,as smart home technology gradually enters our lives,the demand for humidity-sensitive detectors is increasing day by day.Detector stability and detection sensitivity requirements.More importantly,the current popular humidity detectors on the market all have the problem of performance degradation of the humidity sensor under long-term operation,especially in a high humidity environment,this situation will be more prominent,which seriously affects the humidity sensor.Large-scale commercial application.The stability of the humidity sensor directly determines whether it can operate safely and reliably and whether it can accurately detect the humidity of the surrounding environment,which is very important for weather forecasting,physical storage,health monitoring,and people production and life.Therefore,the improvement and improvement of the stability of the humidity detector is of great significance.In recent years,to improve the stability of the humidity sensor,scientific researchers from all walks of life have made many attempts.This paper starts from the performance of the new lead-free perovskite humidity detection material,and discusses the lead-free perovskite humidity sensor.The stability of the pieces is studied.Develop lead-free perovskite humidity sensors with stable structures,and initially explore the application of lead-free perovskite humidity sensors in the field of respiratory monitoring.The main research contents of this paper include:1.Synthesize highly stable,low-cost,non-toxic lead-free perovskite Cs₃Bi₂Br₉ and Cs₂TeCl₆ materials.By improving their synthesis method,the synthesis conditions of humidity-sensitive detection materials were adjusted and the surface defects were passivated to obtain uniform morphology,high stability and lead-free perovskite material.2.Using Cs₃Bi₂Br₉ material under the action of water molecules in an ultra-high humidity environment(relative humidity greater than 90%),a BiOBr material with high water stability is grown on the surface of the Cs₃Bi₂Br₉ perovskite material to synthesize a Cs₃Bi₂Br₉/BiOBr heterojunction humidity detector.The Cs₃Bi₂Br₉/BiOBr heterojunction material has good water stability and can meet long-term and high-stability work.3.The highly stable Cs₂TeCl₆ perovskite material is prepared and successfully applied to the humidity sensor for the first time.The research results show that after the performance of this humidity-sensitive material is degraded in an ultra-high humidity environment,the humidity-sensitive detection performance can be repaired in a very short time through simple HCl gas treatment.And the repaired humidity sensor has the same humidity detection performance as the original,which solves the stability problem of the humidity sensor when the humidity sensor works for a long time and realizes recycling.In the end,preliminary explorations have been carried out on the application of the obtained humidity detector with fast recovery and rapid response in the field of respiratory monitoring.