A novel rare-earth nitronyl nitroxide radical complex as a high-efficiency sensor for Cr³⁺ and Cr₂O₇²⁻ ions in aqueous solutions

Abstract

In this article, a new complex with formula [Eu(hfac)₃(NITPh-DOMe)₂] (1) (hfac =  hexafluoroacetylacetonate, NITPh-DOMe =2-(3′,4′-dioxylmethylene-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide) has been successfully synthesized. Central Eu(III) ions of complex 1 are eight coordinated by two NITPh-DOMe radicals and three hexafluoroacetylacetonate ligands. The luminescent explorations show that complex 1 with high sensitivity, selectivity, almost linear at low concentration and the low detection limit for detection of Cr³⁺ (1 μM) and Cr₂O₇²⁻ (0.1 μM) ions in aqueous solutions.

Keywords:

• Nitronyl nitroxides
• fluorescent sensor
• Cr³⁺ ions
• Cr₂O₇²⁻ ions

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Nos. 21371104, 20771081, 21101096, and 21471084) and Laboratory Innovation Fund (30003) of Tianjin University of Science and Technology.

Supplementary information

CCDC Number 1830897 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge at www.ccdc.cam.ac.uk/conts/retrieving.html or from the Cambridge Crystallographic Data Center, 12, Union Road, Cambridge CB2 1EZ, UK; fax: (internet) +44-1223/336033; E-mail: [email protected].