High Performance Colorimetric Carbon Monoxide Sensor for Continuous Personal Exposure Monitoring

Carbon monoxide (CO) is a highly poisonous gas, which can cause serious health risk. CO monitoring helps protect us from excessive exposure at home and in the workplace, and reduce occupation-related health risks for workers. Conventional electrochemical and metal oxide semiconductors (MOS) based CO sensors have been widely used, but the drawbacks such as poor selectivity and calibration burden also limit their applications, e.g., as wearable exposure monitors. Aiming at the reliable, miniaturized, and easy-to-use personal exposure device development, we report a colorimetric CO sensing platform, which achieves a detection limit of 1 ppm, dynamic range of 0-500 ppm, and high selectivity to CO over common interferents in air, such as CO₂, NO₂, SO₂, and O₃. This optical sensing platform can be expanded to other air pollutants by adding other chemical sensing probes. We believe the new sensing platform we introduced can provide a potential high performance sensing unit for wearable personal exposure assessment devices.