Cd-Ii-Organic Frameworks Fabricated With A N-Rich Ligand And Flexible Dicarboxylates: Structural Diversity And Multi-Responsive Luminescent Sensing For Toxic Anions And Ethylenediamine

Three metal-organic frameworks {[Cd(L)(glu)].3 H2O}(infinity) (1), {[Cd-2(L)(2)(adi)(2)].5 H2O}(infinity) (2) and {[Cd(L)(sub)].3 H2O.DMA }(infinity) (3) (L=pyridine-3,5-bis(5-azabenzimidazole), H(2)glu=glutaric acid, H(2)adi=adipic acid and H(2)sub=suberic acid) were obtained under solvothermal conditions. Complex 1 shows a 2D (4,4) network constructing of Cd-2-glu and Cd-L chains. Complex 2 presents a 2-fold interpenetrating 3D framework with pcu topology. Complex 3 is a 3D framework with cds topology. Three complexes with versatile structures were obtained by changing aliphatic dicarboxylate ligands with different lengths based on a N-rich ligand. Moreover, the fluorescence measurements indicate that complex 1 is a good multifunctional chemosensor for the detection of Cr2O72- and MnO4- anions by fluorescence quenching effect, and ethylenediamine by fluorescence enhancement effect, with detection limits of 1.196 ppm, 0.551 ppm and 64.572 ppm, respectively. Both complexes 2 and 3 can selectively sense Cr2O72- anion with detection limits of 1.126 ppm for 2 and 0.831 ppm for 3 by a fluorescence quenching effect.