Development of a non-resonant photoacoustic gas sensor for CO2 detection

Abstract

Photoacoustic spectroscopy (PAS) is an attractive technique for gas detections and analysis. This study focuses on optimizing a photoacoustic gas sensor by analyzing key structural parameters. Through the establishment of a 3D model, simulations, and subsequent experimental validation, the impact of these parameters on the sensor's performance was explored. This comprehensive approach successfully determined the optimal structural parameters. The photoacoustic gas sensor consists of a micro-electro-mechanical systems (MEMS) emitter, a miniature photoacoustic-cell, a MEMS microphone and a circuit. The footprint of the sensor is approximately 12 mm × 12 mm × 6 mm (length × width × height) which is 10 % of conventional non-dispersive infrared gas sensors. The accuracy of the sensor is ±0.05 % in 0 % to 10 % CO2 concentrations. And the response time (T100) is 80 s. The limit of detection (LOD) in CO2 concentrations is 0.12 %. The power consumption of the sensor is only 44 mW.