Achieving Sub-ppm Sensitivity in SO 2 Detection with a Chemically Stable Covalent Organic Framework

• Published in: Angewandte Chemie International Edition 2024-11, p.e202415088
• Main Authors: Zhao, Wei, Obeso, Juan L, López-Cervantes, Valeria B, Bahri, Mounib, Sánchez-González, Elí, Amador-Sánchez, Yoarhy A, Ren, Junyu, Browning, Nigel D, Peralta, Ricardo A, Barcaro, Giovanni, Monti, Susanna, Solis-Ibarra, Diego, Ibarra, Ilich A, Zhao, Dan
• Format: Article
• Language: English
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202415088

We report the inaugural experimental investigation of covalent organic frameworks (COFs) to address the formidable challenge of SO detection. Specifically, an imine-functionalized COF (SonoCOF-9) demonstrated a modest and reversible SO sorption of 3.5 mmol g at 1 bar and 298 K. At 0.1 bar (and 298 K), the total SO uptake reached 0.91 mmol g with excellent reversibility for at least 50 adsorption-desorption cycles. An isosteric enthalpy of adsorption (ΔH ) for SO equaled -42.3 kJ mol , indicating a relatively strong interaction of SO molecules with the COF material. Also, molecular dynamics simulations and Møller-Plesset perturbation theory calculations showed the interaction of SO with π density of the rings and lone pairs of the N atoms of SonoCOF-9. The combination of experimental data and theoretical calculations corroborated the potential use of this COF for the selective detection and sensing of SO at the sub-ppm level (0.0064 ppm of SO ).