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DOE OSTI · 1981760

Selective acetate recognition and sensing using SWCNTs functionalized with croconamides

Yoon, Bora·Choi, Seon-Jin
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Abstract

Croconamides are a new class of dual-hydrogen bond donors that have attracted interest in anion recognition and sensing applications due to their strong H-bond donation capability. In this work, we report chemiresistive sensors for the detection of anions based on poly(4-vinylpyridine) (P4VP)-wrapped single-walled carbon nanotubes (SWCNTs) functionalized with croconamide-based selectors. Model structures of asymmetric N,N-substituted croconamide selectors with N,N-substitutional groups of alkyl cationic pyridinium and electron-withdrawing moieties such as aniline (6) and 3,5-bis(trifluoromethyl)phenyl (7) groups were synthesized and their binding affinities for various anions were characterized using UV–vis and 1 H NMR titrations. Switchable binding of oxoanions was observed with selector 7, wherein HSO 4 – formed hydrogen bonding interactions and acetate (AcO – ) induced deprotonation of the NH- protons of the croconamide. Large sensitivity transitions were obtained toward AcO – for both P4VP-6-SWCNT (S = 95.68 ± 2.11 %) and P4VP-7-SWCNT (S = 140.91 ± 3.68 %) at 83.33 mM, which was attributed to deprotonation of the croconamide selectors upon addition of AcO – . In conclusion, three serial sensors were assembled in a sensor array that rapid and selective screening of AcO – was demonstrated against other oxoanions such as HSO 4 – and H 2 PO 4 – in real-time.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYAnion sensorChemiresistorChemistryCroconamidesDual-hydrogen bond donorElectrochemistryInstruments & InstrumentationSingle-walled carbon nanotubes

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Yoon, Bora, Choi, Seon-Jin. 2021-07-19. Selective acetate recognition and sensing using SWCNTs functionalized with croconamides. https://doi.org/10.1016/j.snb.2021.130461

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