Europium Activated Aluminum Organic Frameworks for Highly Selective and Sensitive Detection of Fe and Cr(Ⅵ) in Aqueous Solution

The aluminum based MOFs compound, MIL-96(Al), has been studied as a luminescence sensor by incorporating of Eu3+ ions, which renders the compound strong red-light emission. The as-synthesized MIL-96(Al):Eu3+ nanocrystals exhibit water dispersibility and environmental stability, which are general requirement for an ideal sensing material. The MIL-96(Al):Eu3+ nanocrystals show excellent selective detection ability on Fe3+ ions in aqueous solution with value of low detection limit 20 μM. Meanwhile, it also exhibits excellent selective detection ability on CrO42- and Cr2O72- in aqueous solution with value of low detection limit 10 and 22 μM, respectively. The results of this study show that MIL-96(Al):Eu3+ nanocrystals could be used as a multi-responsive luminescent senor for Fe3+ and Cr(Ⅵ) species in aqueous solution. The possible luminescence quenching mechanism has also been discussed.