Terpyridine-based complex nanofibers with Eu as a highly selective chemical probes for UO.

Uranyl is a radioactive, toxic pollutant commonly found in the waste remaining after nuclear fuel reprocessing, and it poses several types of risks to human health; therefore, developing absorbents and chemical probes for this compound is crucial to overcoming these issues. This study examined the sensing abilities of terpyridine-appended benzenetricarboxyamide (T-BTA) as a chromogenic probe for detecting uranyl ions (UO). The complex with Eu (1-Eu) spontaneously formed nanostructured fibers in HO owing to the triamide groups of T-BTA, which induced intermolecular hydrogen-bonding interactions. The strong blue emission of these nanofibers in HO was quenched upon adding UO but not upon adding any other metal ion. This high selectivity was probably because of the interactions between the nitrigen atoms of the terpyridine moieties of 1 and UO. Furthermore, the 1-Eu nanofibers assumed spherical morphologies when UO was added. To develop a convenient UO sensor, an electrospun film incorporating 1-Eu (ESF-1-Eu) was manufactured, and it exhibited high selectivity for UO over a variety of rival metal ions. The plot for luminescence change of ESF-1-Eu vs UO concentrations in seawater samples showed a good linearty. Thus, the ESF-1-Eu shows potential as a useful sensor for detecting and removing UO in HO.