Portable Aromatic VOC Gas Sensor for Onsite Continuous Air Monitoring wuth 10-ppb Benzene Detection Capability

摘要

We have developed a portable gas sensor using microfluidic devices (concentration and detection cells) for detecting and identifying gaseous aromatic volatile organic compounds (VOCs), such as benzene, toluene, xylene, styrene, and ethylbenzene. To improve the sensor's sensitivity, we introduced techniques for the precise control of gas transfer from the concentration cell to the detection cell and optimized the spectrum measurement conditions. We achieved a detection level of 10 ppb for benzene gas as an example of aromatic VOC detection in a sampling time of 50 minutes. The calibration curve showed good linearity in the range of 10?100 ppb of benzene. We also carried out gas-monitoring experiments in a garage. The results show the applicability of our aromatic VOC sensor for field monitoring.