3D water-stable europium metal organic frameworks as a multi-responsive luminescent sensor for high-efficiency detection of Cr <sub/>2</sub> O <sub/>7</sub>^2? , MnO <sub/>4</sub>^? , Cr ³⁺ ions and SDBS in aqueous solution

摘要： A microporous europium metal–organic framework (Eu-MOF), namely, {[Eu3(bpydb)3(HCOO)(OH)2(DMF)]·3DMF·2H2O}n (1) with asymmetric trinuclear metal clusters extended by 4,40-(4,40-bipyridine-2,6-diyl) dibenzoic acid has been synthesized via the solvothermal method. PXRD of 1 confirms that it possesses excellent water stability and pH stability. The photo-luminescence properties of 1 exhibit effective recognition of Cr2O72?, MnO4?, and Cr3+ ions and SDBS. Furthermore, a wide linear range, high quenching constant and a low detection limit reveal that 1 can potentially act as a luminescence-based sensor for quantitative and highly sensitive detection of Cr2O72?, MnO4?, and Cr3+ ions as well as SDBS in aqueous solutions. To the best of our knowledge, the detection limit of 1 is the lowest value reported for Ln-MOF-based luminescent sensors to detect Cr2O72? ions (0.5 mM) in aqueous solutions. The use of a rare earth fluorescent probe for detecting MnO4? ions is not common. It is the first time that Ln-MOF as a fluorescence probe is used for detecting SDBS. Moreover, fluorescent-based test papers of 1 have also been prepared, which can be helpful to develop visual detection for Cr2O72?, MnO4?, and Cr3+ ions as well as SDBS in daily applications.