A Design of Acoustic Catalytic Sensing System for Trace Gas Detection

Abstract

Our research team proposed and developed an acoustic catalytic method to enhance the sensing performance of gas sensors. In this work, the design method for an acoustically catalyzed metal oxide (MOX) gas sensor system is investigated for low concentration target gas detection. A sensor control system, which is based on the real-time operating system FreeRTOS and cooperates with hardware such as the signal generation, power amplification and impedance matching circuits, is implemented with the functions of generation and assignment of the tasks such as excitation of ultrasonic transducer, data acquisition of MOS sensor and current feedback control. One-click operation, and real-time data display and saving in the experimental process are realized by the LabVIEW. The experimental results show that the designed system can significantly improve the sensitivity of the MOX gas sensor, and reduce its lower detection limit.