Two cadmium(II) coordination polymers constructed from dicarboxylate and bis(imidazole) ligands: Syntheses, crystal structures, luminescence and photocatalytic properties

•Two novel cadmium(II) coordination polymers were prepared under hydrothermal conditions.•The significant discrepancy of their network structures may be attributed to the fluorinated substituent group.•The two complexes present good photocatalytic activities in methylene blue (MB) degradation reactions.

Two cadmium(II) coordination polymers, namely Cd4(DPA)4(BIMB)2·H2O (1) and Cd2(DPA)2(FBIMB)2·H2O (2), where H2DPA = diphenic acid, BIMB = 1,4-bis(imidazol-1-yl-methyl)benzene and FBIMB = 2,3,5,6-tetrafluoro-1,4-bis(imidazol-1-yl-methyl)benzene, have been synthesized under hydrothermal conditions and characterized by IR, elemental analyses and single crystal X-ray diffraction. Structural analyses reveal that complex 1 features a two-dimensional (2D) layer structure based on one-dimensional (1D) Cd-DPA chains, while complex 2 exhibits an interesting three-dimensional (3D) 4-connected network with (65.8) topology. A careful structural comparison reveals that the similarity of the Cd(II) coordination geometry and ligand binding mode, but the significant discrepancy of their network, which may be attributed to the fluorinated substituent group. Two complexes indicate high thermal stabilities and different photoluminescence behavior in the solid state. Moreover, two complexes present good photocatalytic activities in methylene blue (MB) degradation reactions.

Graphical abstractTwo novel cadmium(II) coordination polymers, namely Cd4(DPA)4(BIMB)2·H2O (1) and Cd2(DPA)2(FBIMB)2·H2O (2), have been synthesized under hydrothermal conditions and characterized by IR, elemental analysis and single crystal X-ray diffraction. Complex 1 features a two-dimensional (2D) layer structure based on one-dimensional (1D) Cd-DPA chains, while complex 2 exhibits an interesting three-dimensional (3D) 4-connected network with (65.8) topology. The significant discrepancy of their network structures may be attributed to the fluorinated substituent group. Two complexes indicate high thermal stabilities and different photoluminescence behavior in the solid state. Moreover, two complexes present good photocatalytic activities in methylene blue (MB) degradation reactions.Figure optionsDownload full-size imageDownload as PowerPoint slide