Europium(III) metal-organic framework as a fluorescent probe for selectively and sensitively sensing Pb2+ in aqueous solution

A novel europium metal-organic framework (Eu-MOF) with formula (H3O)(6)[Eu(BHC)(H2O)](2)center dot H2O (1) has been synthesized successfully via the hydrothermal method by using a monoaromatic polycarboxylic acid ligand benzenehexacarboxylic acid (H6BHC) reacting with Eu(NO3)(3)center dot 6H(2)O. Single-crystal X-ray diffraction analysis reveals that in 1 the adjacent two Eu(III) cations are bridged by the BHC6- ligands to form the Eu dinuclear unit as a node, and then the Eu dinuclear nodes join each other via the BHC6- as bridges plus the hydrogen bond interactions along a-, b- and c-axis to form a unique 3D network structure. Photoluminescence measurement indicates that 1 possesses the following advantages as the fluorescent probe: 1 displayed a very low limit of detection ( LOD) for Pb2+ (0.42 mu mol center dot L-1) in an aqueous system, and 1 demonstrated higher selectivity. CCDC: 2299340, 1.