Title
Two Uranyl Heterocyclic Carboxyl Compounds with Fluorescent Properties as High Sensitivity and Selectivity Optical Detectors for Nitroaromatics
Author
Shuang Li, Li Xian Sun, Jue Chen Ni, Zhan Shi, Yong Heng Xing, Di Shang, Feng Ying Bai
Year
2017
Journal
New Journal of Chemistry
Abstract
The two compounds, UO2(C16H7N4O4)2·2H2O (1) and UO2(C20H12N5O2)2 (2) have been synthesized, based on the different heterocyclic carboxyl ligands, 2,3-pyrazino[1,10]phenanthroline-2,3-dicarboxylic acid (H2L1) and 2,6-bis(2- pyrazinyl)pyridine-4-benzoic acid (HL2). Two compounds were characterized by the elemental analysis, IR spectroscopy, PXRD, thermogravimetric analysis and UV-vis Spectroscopy. The single crystal X-ray diffraction analysis revealed that both compounds 1 and 2 exhibited 2D sheet structures. Moreover, the study of fluorescence quenching properties of compounds 1 and 2 showed that the luminescent intensity decrease for both 1 and 2 were especially obvious with the increasing of the nitroaromatics concentration, even if the nitroaromatics were at a very low concentration (for 1 is 15 ppm, for 2 is 20 ppm), which can also be detected. The experimental results suggest a high selective quenching of initial fluorescence intensity in the presence of nitroaromatic compounds. And by calculating the quenching constants of the nitroaromatics using the SV equation (I0/I) = KSV[A] + 1, we can see the KSV values of the quencher TNP are both largest for two compounds, and the values are 1.6×106 and 8.5×105 for 1 and 2, respectively. It means that the two compounds are of the best sensitive luminescence. In addition, compound 2 exhibit enhanced fluorescence behavior towards to aldehyde compounds, showing a turn-on fluorescence responsive behavior.
Instrument
FP-6500
Keywords
Fluorescence, Photoluminescence, Inorganic chemistry, Solid state, Quenching, Materials