Copper-Based Two-Dimensional Conductive Metal–Organic Framework Thin Films for Ultrasensitive Detection of Perfluoroalkyls in Drinking Water
Heejung Roh, Tyler J. Quill, Gan Chen, Huaxin Gong, Yeongsu Cho, Heather J. Kulik, Zhenan Bao, Alberto Salleo, Aristide Gumyusenge
Abstract
Perfluoroalkyls (PFAS) continue to emerge as a global health threat making their effective detection and capture extremely important. Though metal-organic frameworks (MOFs) have stood out as a promising class of porous materials for sensing PFAS, detection limits remain insufficient and a fundamental understanding of detection mechanisms warrants further investigation. Here, we show the use of a 2D conductive MOF film based on copper hexahydroxy triphenylene (Cu-HHTP) to fabricate chemiresistive sensing devices for detecting PFAS in drinking water. We further show ultrasensitive detection using electrochemical impedance spectroscopy. Owing to excellent electrostatic attractions and electrochemical interactions between the copper-based MOF and PFAS, confirmed by high-resolution spectroscopy and theoretical simulations, the MOF-based sensor reported herein exhibits excellent affinity and sensitivity toward perfluorinated acids at concentrations as low as 0.002 ng/L.