A dual luminescent chemosensor derived from a europium(III) metal-organic framework for quantitative detection of phosphate anions and acetylacetone in aqueous solution

Abstract

A luminescent europium(III) metal-organic framework (MOF) {[Eu(bcpt)(HCOO)]·0.5H2O}n (1) has been synthesized under solvothermal conditions by adopting a elongated ligand encompassing three aromatic rings groups, 3,5-bis(4′-carboxy-phenyl)-1,2,4-triazole (H2bcpt). This MOF demonstrates a binodal (4,10)-connected framework with a Schläfli symbol of {34·42}{38·414·516·67}, in which the adjacent Eu(III) ions can be bridged by HCOO− anions to form a 2D layer and further connected by H2bcpt as a pillar to generate a 3D pillared-layer structure. Notably, such a binodal (4, 10)-connected topological structure is rarely explored in MOF family, particular of lanthanide(III) MOF chemistry. Furthermore, 1 could be exploited as a dual luminescent chemosensor to probe PO43− anions and acetylacetone in aqueous solution with the average quenching Ksv values of 1.27 × 104 L mol−1 and 322 L mol−1, and the detection limits of 2.74 × 10−4 mol L−1 and 1.21 × 10−4 mol L−1, respectively.