Choi, Seung-Ho Lee, Joon-Seok Lee, Sungju Jeong, Hyeon Su Choi, Seon-Jin 2024-10-26T06:30:27Z 2024-10-26T06:30:27Z 2024-10-25 2025-02 1613-6810 https://pubs.kist.re.kr/handle/201004/150856 In this study, chemiresistive anion sensors are developed using carbon nanotube fibers (CNTFs) functionalized with squaramide-based dual-hydrogen bond donors (SQ1 and SQ2) and systematically compared the sensing properties attained by two different functionalization methods. Model structures of the selectors are synthesized based on a squaramide motif incorporating an electron-withdrawing group. Anion-binding studies of SQ1 and SQ2 are conducted using UV-vis titrations to elucidate the anion-binding properties of the selectors. These studies revealed that the chemical interaction with acetate (AcO-) induced the deprotonation of both SQ1 and SQ2. Selectors are functionalized onto the CNTFs using either covalent or non-covalent functionalization. For covalent functionalization, SQ1 is chemically formed on the surface of the CNTFs, whereas SQ2 is non-covalently functionalized to the surface of the CNTFs assisted by poly(4-vinylpyridine). The results showed that non-covalently functionalized CNTFs exhibited a 3.6-fold higher sensor response toward 33.33 mm AcO- than covalently functionalized CNTFs. The selector library is expanded using diverse selectors, such as TU- and CA-based selectors, which are non-covalently functionalized on CNTFs and presented selective AcO--sensing properties. To demonstrate on-site and real-time anion detection, anion sensors are integrated into a sensor module that transferred the sensor resistance to a smartphone via wireless communication. The effective electrical transduction property of chemiresisitve anion sensors is elucidated by comparing the functionalization techniques of selectors onto the carbon nanotube fiber (CNTF). Various dual-hydrogen bond donor-based selectors are developed and functionalized either covalently or non-covalently to evaluate acetate sensing response. Much improved acetate sensing performance is achieved by non-covalent selector functionalization with the demonstration of real-time wireless detection of acetate using a mobile device. image English Wiley - V C H Verlag GmbbH & Co. Dual-Hydrogen Bond Donor-Functionalized Carbon Nanotube Fibers: Enhancing Anion-Sensing Performance Through Functionalization Approaches Article 10.1002/smll.202405070 1 Small, v.21, no.6 Small 21 6 Y scie scopus 001329634400001 2-s2.0-85205844629 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article NONCOVALENT FUNCTIONALIZATION ACETATE RECOGNITION RECEPTORS SQUARAMIDE CROCONAMIDES SPECTROSCOPY IMIDAZOLIUM SENSORS anion carbon nanotube fiber chemiresistive sensor deprotonation Dual-hydrogen bond donor