Oximation reaction induced reduced graphene oxide gas sensor for formaldehyde detection

High-performance gas sensors can offer great potentials for monitoring and detection ofvolatile organic compounds (VOCs) in both domestic and industrial environment. In the presentwork, a new HCHO gas sensor was constructed with reduced graphene oxide (RGO) induced bythe oximation reaction. The gas-sensing performance test results suggested that the RGO hydrox-ylamine hydrochloride (RGO/HA-HCl) sensor presented a high response of 75% at 16 ppm HCHOat room temperature, and a high selectivity for HCHO suffering little interference with high concen-trations of volatile organic compounds, including methanol, ethanol, and methylbenzene, dichlor-omethane and water. Additionally, the RGO/HA-HCl sensor also showed a good long-termstability with RSD of 5.83% for a 15-day continuous sensing test, and the detection limit (DL)could reach 0.023 ppm under ambient conditions. Moreover, the mechanism for the high sensitivityand selectivity of formaldehyde was further established by in-situ gas chromatography mass spec-trometry (GC–MS). This work would provide a reliable new HCHO gas sensor which could be usedfor monitoring and forewarning the emission of HCHO for a better protection and improvement ofour environment.