Broadband Dielectric Spectroscopic Detection of Aliphatic Alcohol Vapors with Surface-Mounted HKUST-1 MOFs as Sensing Media

• DOI: 10.3390/chemosensors10100408
• Publication Date: 2022-10-11T01:07:11Z
• Authors: Papa K. Amoah; Zeinab Mohammed H...; Rhonda R. Franklin; Helmut Baumgart; Engelbert Redel; Yaw S. Obeng
• Keywords: 570; TCNQ-HKUST-1 SURMOF; Thin film sensing material; HKUST-1 metal–organic framework (MOF) sensing material; Broadband dielectric microwave spectroscopy; QD415-436; Physical Chemistry; Biochemistry; 01 natural sciences; broadband dielectric microwave spectroscopy; Organic framework (MOF) sensing material; info:eu-repo/classification/ddc/570; broadband dielectric microwave spectroscopy; TCNQ-HKUST-1 SURMOF, thin film sensing material; HKUST-1 metal–organic framework (MOF) sensing material; aliphatic alcohol vapor detection; VOC detection; VOC detection; biology; Electrical and Computer Engineering; Life sciences; 0104 chemical sciences; Detection; TCNQ-HKUST-1 SURMOF, thin film sensing material; Aliphatic alcohol vapor; ddc:570; HKUST-1 metal; aliphatic alcohol vapor detection

We leveraged chemical-induced changes to microwave signal propagation characteristics (i.e., S-parameters) to characterize the detection of aliphatic alcohol (methanol, ethanol, and 2-propanol) vapors using TCNQ-doped HKUST-1 metal-organic-framework films as the sensing material, at temperatures under 100 °C. We show that the sensitivity of aliphatic alcohol detection depends on the oxidation potential of the analyte, and the impedance of the detection setup depends on the analyte-loading of the sensing medium. The microwaves-based detection technique can also afford new mechanistic insights into VOC detection, with surface-anchored metal-organic frameworks (SURMOFs), which is inaccessible with the traditional coulometric (i.e., resistance-based) measurements.