A highly sensitive fluorescent sensor for Al3+ detection based on luminescent Eu(III)-β-dicetonate complexes

Abstract

The structure of the Eu(III) complexes were determined by single-crystal X-ray diffraction. The results showed that these complexes exist as a heteronuclear of Eu(III)-Na(I) in which ion Eu³⁺ is coordinated through eight oxygen atoms of four β-dixetone ligands. The authors found that the monomeric europium-sodium complex displays a very strong red emission with a quantum yield up to 47.5% at λ_ex=370 nm. The authors have successfully designed a simple process to put the Eu(III) complexes on anion exchange resin to create Resin-EuTFNB and Resin-EuTFPB materials. The products have a luminescent intensity that is stronger than that of the precursor complexes due to the removal of the coordination solvents in these complexes. Initially, using these materials to test the ability to recognise Al³⁺ ion at low concentrations, Resin-EuTFNB and Resin-EuTFPB played a role as a sensing chemosensor based on turn-off mechanism. In the future, they are expected to detect Al³⁺ ion in the biological system.