Two Eu(III) central silica hybrids as ratiometric turn-on luminescent sensors for Al3+ ions

Abstract

Aluminum ion is considered as an important ecological pollution because of its wide application in industry. In addition, excessive aluminum ion in water and food will cause great harm to human body. Therefore, it is very important to develop highly sensitive and selective sensors for the detection of aluminum ions. In this work, two kinds of β - diketone ligands (4, 4, 4-trifluoro-1-(2-naphthyl)–1, 3-butanedione (NTA) and 2-thiophenyltrifluoroacetone (TTA)), which have good energy matching with europium ion, are selected as the first ligands, and they are covalently grafted onto the silica network through reactions with triethoxysilyl propyl isonitrile, and then p-bromobenzotripyridine (L) is used as the second ligand. Finally two rare earth europium organic–inorganic hybrid materials, Eu(NTA-Si)3L and Eu(TTA-Si)3L, were obtained by coordination reaction and hydrolytic copolycondensation. Their luminescent properties and cation sensing properties were further studied. Two kinds of rare earth europium organic–inorganic hybrid materials not only display excellent photoluminescence properties, but also have excellent performance in the detection of aluminum ions in THF solution.