Morphology design and control of a novel 3D potassium metal-organic coordination polymer compound: Crystallography, DFT, thermal, and biological studies

New Three-Dimensional Supramolecular Framework: Crystal Structure and Photocatalytic Property

In this work, benzimidazole (Hbim) and Cu(II) ions ligands were chosen as building blocks to produce a novel Cu(II) compound (CP) based on {Cu4O}cluster, namely, [Cu4OCl6(Hbim)4]n·n(H2O)·2n(EtOH) (1). The investigation of SCXRD reveals that the CP 1 is a separated 0D structure based on tetrahedral {Cu4O} clusters. Furthermore, this supramolecular frame displayed superior photocatalytic effect on the photodegradation of MB under UV light irradiation.

A core/shell TiO2 magnetized molecularly imprinted photocatalyst (MMIP@TiO2): synthesis and its photodegradation activity towards sulfasalazine

Although the selectivity of TiO₂ for the degradation of target molecules is not enough, it is a broadly employed photocatalyst for the degradation of many pollutants. Molecularly imprinted compounds owing to their extreme recognition specificity have become increasingly popular for preparing selective photocatalysts. In this work, based on molecularly imprinted magnetized TiO₂ (MMIP@TiO₂), a selective photocatalyst was prepared. Via the co-precipitation method, Fe₃O₄ particles were prepared and coated respectively by SiO₂, vinyl end groups, and molecularly imprinted polymers (MIP). The synthesized photocatalyst was characterized by the X-ray diffraction method (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive x-ray spectrometry (EDX), vibrating sample magnetometry (VSM), high-performance liquid chromatography (HPLC), and photoluminescence analysis (PL). The photocatalyst was then used to degrade the sulfasalazine pharmaceutical pollutant under UV irradiation. An average crystallite size of 9 nm was obtained for the MMIP@TiO₂ sample from the Scherrer formula and 34.5 nm by the Williamson-Hall formula. The results revealed that compared to the non-imprinted counterpart, the molecularly imprinted photocatalyst had significantly higher efficiency and selectivity for the degradation of target molecules. The process was forwarded with 90% efficiency within 10 min. Optimal conditions were 10.0 min irradiation when 25 mL SSZ solution (50 mg/L), 0.07 g/L catalyst dose, and pH 6.0 were applied. The maximum removal efficiency was calculated to be 92%. The external magnetic field quickly removed the photocatalyst from the solution and regenerated it. It was revealed that after each regeneration cycle, the efficiency dropped. Nevertheless, 63% of the preliminary effectiveness remained after four regeneration steps.

New 3D Supramolecular Framework: Photocatalytic Property and Therapeutic Activity on Orbital Wall Fracture

Coordination compounds have undergone booming development in the past 20 years for their applications as multifunctional materials in the field of catalysis and biomedicine. To create compounds with both catalytic and bioactive properties, we selected Cu(II) ion and benzimidazole (Hbim) ligand as the building blocks to fabricate a new cluster-based Cu(II) compound [Cu4OCl6(Hbim)4]n·n(H2O)·2n(EtOH) (1). The exploration of single crystal X-ray diffraction exhibits that complex 1 is a 0D isolated structure on the basis of tetrahedral {Cu4O} clusters. Moreover, such supramolecular framework not only shows excellent photocatalytic effect for the MB photodegradation under the irradiation of ultraviolet light but also has the application values against orbital wall fracture. This work gives new insights on the creation of coordination polymers which might be potentially used as photocatalytic and bioactive reagents.

Structural characterization of sodium and potassium 3-nitrohydrogenphthalate coordination polymers

The synthesis, crystal structures and properties of two alkali metal 3-nitrohydrogenphthalates obtained by a 1:2 reaction of M2CO3 (M = K or Na) with 3-nitrophthalic acid (LH2) are reported. In the anhydrous potassium coordination polymer [K(LH)] (LH = 2-carboxy-3-nitrobenzoate) 1, the K+ cation is bonded to nine oxygen atoms from six symmetry related (LH)– ligands resulting in a distorted {KO9} coordination polyhedron. Five of the six oxygen atoms including a nitro oxygen atom of the crystallographically unique 2-carboxy-3-nitrobenzoate are involved in metal binding. The μ6-bridging mode of (LH)– places the K+ cations into the layers of the two-dimensional (2D) coordination polymer. Each {KO9} polyhedron in 1 shares edges with two other polyhedra along the b and c axes. A low temperature structure redetermination of [Na(L#H)(H2O)3]·H2O (L#H = 2-carboxy-6-nitrobenzoate) 2 has revealed that the (L#H)− anion is bonded to the Na+ cation in a monodentate fashion via the carbonyl oxygen atom of the –COOH group and two of the three unique aqua ligands exhibit a bridging bidentate mode stabilizing a chain polymer. The structure of compound 2 thus consists of chains of edge-sharing {NaO6} octahedra. Thermal decomposition of 1 or 2 results in the formation of metal carbonate residues.

A newly-constructed hydrolytically stable Co(ii) coordination polymer showing dual responsive fluorescence sensing of pH and Cu2+

A novel CP (1), showing distinct dual responsive fluorescence sensing of pH in three continuous stages as well as efficient and selective sensing of Cu²⁺.