Preparation And Performance Research Of Gas Sensor Based On Polymer/MXene Composite Materials

In recent years,due to the need for air quality monitoring,food safety and public health care,the demand for high-sensitivity gas sensors that can be used to effectively detect toxic and harmful gases is increasing in modern society.However,common semiconductor sensors on the market still have some key problems,such as high operating temperature,low sensitivity,and short lifetime.Therefore,it is very important to develop a room temperature gas sensor with high sensitivity,wide detection range,high selectivity,and good stability for detecting toxic and harmful gases.In this paper,based on the excellent gas sensing properties of the two-dimensional material MXene,it is combined with conductive polymer materials and metal oxides to prepare two high-performance room temperature gas sensors.The specific research content is as follows:1.The degradable fiber membrane was prepared by electrospinning PLA/PCL nanofiber,and the 2D MXene was coated on the surface of the fiber membrane by Plasma treatment,and then PANI was coated on the surface of MXene by soaking polyaniline to prepare interconnected network structure MXene/PANI composite fiber membrane.The sensor assembled by MXene/PANI composite fiber membrane shows excellent response performance and stability to ammonia.The response time of the sensor to 100 ppb NH₃ is 42 s and the recovery time is 48s,the detection range of the sensor is 0.1-100ppm at room temperature.The sensor can identify NH₃ in a complex gas environment with good selectivity.The sensor also has excellent stability,can be used for a long time,and can work stably under different humidity conditions.2.The interconnected frame is constructed by electrospinning polyacrylonitrile(PAN)fibers on the surface of the gauze window as the flexible substrate of the sensor,then the two-dimensional material MXene is treated by surface oxidation to generate TiO₂ on the surface in situ to prepare the TiO₂/MXene nanocomposite material.MXene can be coated on the surface of PAN through supramolecular interaction to form a three-dimensional network sensing film.The TiO₂/MXene three-dimensional network sensing film is assembled into a gas sensor,which can detect NO₂ at room temperature.The sensor can detect NO₂ gas with a concentration in the range of 0.5-10 ppm,and shows excellent sensor response,cycle stability and selectivity.