Rapid Detection of ppt Concentration of Perfluorooctane Sulfonate in Water by Quartz Crystal Microbalance Loaded with MOF-808

Abstract Identifying trace levels of perfluorooctane sulfonate (PFOS) at parts per trillion (ppt) in water remains a formidable task. Here, we fabricated MOF-808 through rapid microwave synthesis. Characterization of the synthesized MOF-808 involved techniques including XRD, FT-IR, SEM, and nitrogen sorption analysis. We integrated the MOF-808 as the sensing layer in a quartz crystal microbalance (QCM) sensor, specifically tailored for PFOS detection in water. Our findings revealed that the QCM sensor can detect 10 ppt of PFOS when the frequency shift is approximately 90 Hz within 50 s. Moreover, the continuous response, selectivity, and anti-interference capability of the sensor were systematically explored. This study introduces a pioneering approach for detecting ppt concentrations of PFOS in water, offering significant prospects for future applications and dissemination.