Construction And Response Performance Of Pattern Recognition Gas Sensor For Flammable Gas

Oxide semiconductor-based gas sensors have received widespread attention in the detection of flammable and explosive gases due to their quick response,high sensitivity,and low cost.However,in actual gas detection applications,oxide gas sensor is susceptible to interference from other reducing gas,resulting in detection abnormalities such as false detections and false alarms.Therefore,how to realize the effective identification and detection of complex flammable gases by oxide-based semiconductor-based gas sensors has become a major challenge in current research.In this work,we attempts to use pattern recognition technology to analyze the differential response signals of multiple gas sensors to realize the judgment and detection of complex gas components.For the three model reducing gases of H₂,CO and CH₄,first,we constructed oxide nanomaterials of different types and morphologies,and studied the cross-sensitivity of the material response behavior.Second,using Pd and Au nanoparticles to modify the surface of Sn O₂,ZnO nanomaterials,which improves the identifiability of the gas-sensitive material to H₂,CO,and CH₄ gas.Use Pd/Sn O₂ nanosheets,Au/Sn O₂ nanoparticles,Au/ZnO nanosheets-assembled microspheres and Pd/ZnO nanorods to construct gas sensors,and conduct a large number of gas sensitivity tests on different concentrations H₂,CO,CH₄,and their mixed gases,and collect its respond data.Use the gas analysis program edited by Python software to perform Principal Component Analysis on a large number of characteristic data obtained,and then performs Back Propagation to train the Principal Component Analysis results to realize the component recognition and component concentration determination of the mixed gas.The electronic nose detection system was constructed by using the above four gas sensors and analysis system,and preliminarily evaluated the system's ability to recognize and detect mixed gases of different concentrations.The results show that the system can realize the identification and content detection of effective components in the mixed atmosphere of H₂,CO,and CH₄ in the concentration range of 10-3000ppm,and the detection accuracy of the component concentration is greater than 90%.This research work provides experimental and theoretical basis for the design and development of array gas sensors.