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Photocatalytic degradation of pollutants is an effective environment purification strategy. Metal-organic frameworks (MOFs) have attracted extensive attention in the field of photocatalysis owing to their structural diversity, uniform cavity, and large specific surface area. However, poor electrical conductivity, light absorption, and water stability restrict their development. The tailorable structure of MOFs may effectively overcome these limitations. Herein, three Cu-based MOFs (complexes 1 - 3 ) with one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) structures, respectively, were successfully prepared by introducing different uncoordinated ligands and adjusting the ligand/metal salt ratio. Among them, complex 1 with a 1D chain was constructed as a typical J-type aggregation by π-π stacking interactions between adjacent naphthalene rings. This intermolecular aggregation mode enhances strong exciton coupling between conjugated rings, reduces the transition energy, expands the intrinsic light absorption edge, and provides a channel for electron transport, thus improving the charge-separation efficiency. As expected, complex 1 with a 1D chain structure exhibited excellent Fenton-like catalytic activity. The apparent reaction rates were 3.2 and 2.0 times higher than those of 2D and 3D MOFs, respectively.

Molecule-based solid-state materials with long lifetimes could enable longer migration distances for excitons, which are beneficial for vast applications in optoelectronic field. Herein, we report a hexanuclear zinc cluster based MOF exhibits highly enhanced phosphorescence about 2 orders of magnitude in comparison with the pristine phosphor ligand. The combination of both experimental and computational results suggest that the {Zn 6 } cluster is very important for adjusting molecular conformations, packing arrangement, and photophysical properties of the organic phosphor ligands within the MOF matrix. Optoelectronic measurements reveal that the MOF-modified electrode is catalytically active to hydrogen evolution under light irradiation in neutral solution. Thus, our study provide an effective way to achieve low-cost metal-based phosphorescence MOF, expanding its further optoelectronic applications.

Two unprecedented 2D coordination polymers with 4- and 6-connected topological nets, arising from the different linkages of two adjacent 4(4) layers, were prepared from Co(II), 1,3-bis(4-pyridyl)propane, and different isophthalate tectons.

A series of interesting Co(II)-H(2)tbip coordination polymers incorporating different auxiliary ligands, {[Co(tbip)(bipy)(H(2)O)(3)] x 0.5(bipy) x H(2)O}(n) (1), [Co(tbip)(bipy)](n) (2), {[Co(3)(tbip)(3)(dpe)(3)] x 0.5(dpe) x 3 H(2)O}(n) (3), [Co(2)(tbip)(2)(dpe)(H(2)O)](n) (4), [Co(2)(tbip)(2)(bpa)(H(2)O)](n) (5), and {[Co(2)(tbip)(2)(bpa)(2)] x 2.5 H(2)O}(n) (6) (H(2)tbip = 5-tert-butyl isophthalic acid; bipy = 4,4'-bipyridine; dpe = 1,2-di (4-pyridyl)ethylene; bpa = 1,2-bi(4-pyridyl)ethane) were synthesized. X-ray structural analyses of 1-6 reveal a diverse range of structures, ranging from 1D (1) to 2D (2, 6) to 3D (3, 4, 5). Complex 1 shows 1D zigzag bipy-bridged polymeric chains with the terminal tbip ligands as pendants, which are extended to a 3D hydrogen-bonded supramolecular framework involving 1D open channels which encapsulate guest bipy molecules. Polymers 2 and 6 feature similar 2D infinite layer frameworks consisting of cobalt dimers. The structure of 3 is constructed from [Co(2)(tbip)(2)](n) layers, which consists of alternating left- and right-handed helical chains, and further pillared by dpe ligands into a 3D six-connected self-penetrating 4(8).6(6).8 network. The prominent cavities in 3 are parallel to the (101) plane and encapsulate free dpe as guest molecules. Polymers 4 and 5 are isostructural, showing 2-fold interpenetrating 3D alpha-Po networks constructed from binuclear cobalt nodes. The thermal stabilities and X-ray powder diffraction studies indicate that the framework of 3 can keep stable after the loss of guest molecules. Studies of the magnetic susceptibilities of 2-6 reveal weak antiferromagnetic exchange interactions between adjacent Co(II) centers.

The first azide(mu1,1)-bridged binuclear cobalt(II) complex with a chelated imino nitroxide radical, [Co2(immepy)2(N3)(4)].2EtOH, was structurally and magnetically characterized, where immepy = 4,4,5,5-tetramethyl-2-(6'-methyl-2'-pyridyl) imidazoline-1-oxyl. Five nitrogen atoms complete the coordination sphere of the Co(II) ion, showing a distorted trigonal bipyramid geometry. Two N(3)(-) anions act as bridges between cobalt ions in the mu1,1 coordination mode, resulting in a binuclear structure with an inversion center. Magnetic studies show that ferromagnetic couplings occurred between the adjacent cobalt(II) ions through N3(-)(mu1,1)) bridges, and antiferromagnetic couplings between the cobalt(II) ions and organic radicals.