Post modification of zinc based coordination polymer to prepare Zn-Mo-ICP nanoparticles as efficient self-supported catalyst for olefin epoxidation

Lanthanide coordination polymers@CuO nanoparticles: Enhanced self-cascade nanoenzyme activity and ratiometric fluorescence assay of glutathione

Tandem enzyme can catalyze some cascade reactions with high efficiency, and some few tandem enzyme-like mimics have been discovered recently. Further improving the catalytic efficiency of tandem nanoenzymes with facile method may undoubtedly promote and broaden their applications in various fields. In this work, cupric oxide nanoparticles (CuO NPs) with dual-functional enzyme mimics were synthesized using the rapid deposition method in advance, which simultaneously combined with lanthanide infinite coordination polymers (Ln ICPs) during the self-assemble of Tb3+, guanine-5'-triphosphate (GTP) and auxiliary ligand terephthalic acid (TA). Excitingly, the obtained Tb-GTP/TA@CuO ICPs, not only displayed obviously enhanced tandem catalytic activity compared with pure CuO NPs, but also provided a versatile ratiometric platform for ultrahigh selective and sensitive detection of glutathione (GSH) under single-wavelength excitation. A good linear relationship between the ratio signal and the GSH concentration was spanning from 0.001 to 20 μM with an impressive detection limit of 0.50 nM. This study opens a new and universal avenue for preparing integrated multifunctional probes by coupling of nanoenzyme catalytic activity with superior luminescent Ln ICPs through facile method.

Dual-Ligand Strategy for the Design and Construction of a Cd-Zn Heterometallic Metal-Organic Framework by One-Pot Synthesis as a Heterogeneous Catalyst for the Epoxidation Reaction of Olefins

The use of metal-organic frameworks (MOFs) as catalysts is reported in various industrial applications. In contrast to monometallic MOFs, heterometallic MOFs with mixed organic ligands showed enhanced catalytic properties. The catalytic properties of heterometallic MOFs can be enhanced by generating defects and the synergistic effect between the two heterometals at secondary building units. By using a solvothermal technique, a Cd-Zn heterometallic MOF with a new morphology, [Cd2Zn(DPTTZ)0.5(OBA)3(H2O)(HCOOH)] (IUST-4) [DPTTZ = 2,5-di(4-pyridyl)thiazolo[5,4-d]thiazole, OBA = 4,4'-oxybis(benzoic acid)], was synthesized via a mixed-ligand strategy and characterized by single-crystal and powder X-ray diffraction, Fourier transform infrared spectroscopy, elemental analysis, and thermogravimetric analysis. X-ray crystallographic analysis showed that IUST-4 is a neutral 3D metal-organic framework crystallized in the monoclinic system with space group C2/c. In this study, the catalytic properties of IUST-4 for the epoxidation of cyclooctene were investigated. IUST-4 was selected as the optimal catalyst for epoxy product production due to its high selectivity and yield. Moreover, the catalytic performance of IUST-4 was maintained despite five recycling cycles without significant degradation. The epoxidation of cyclooctene with IUST-4 has several advantages, including good selectivity, easy recovery, and short-time reaction.

Sustainable Coordination Polymer-Based Catalyst and Its Application in the Nitroaromatic Hydrogenation under Mild Conditions

Nitroarene reduction has played a crucial role in the environment remediation and public health. However, few research studies have been undertaken regarding the use of infinite coordination polymer-based catalysts in this process. Herein, we are looking for a way to catalyze the reduction of nitroarenes using a new and well-designed coordination polymer-based palladium catalyst. The Co-BDC-NH₂ coordination polymer was prepared through a co-precipitation reaction between 2-amino-1,4-benzenedicarboxylic acid as a linker and the cobalt cation as a node. Functionalization of the prepared Co-BDC-NH₂ with 2-pyridinecarboxaldehyde and subsequent metallation with a Pd cation led to the formation of the final catalyst, i.e., Co-BDC-NH₂-py-Pd. It has been specified that palladium species substantially contribute to the reduction of nitroarenes in the presence of hydrazine hydrate (N₂H₄·H₂O). The highest conversion (100%) of nitroarenes to the corresponding amines was achieved under relatively mild conditions. This heterogeneous catalyst was able to catalyze the reduction of nitroarenes to desired products without changing other substituents. The reusability and stability of the catalyst were confirmed through four consecutive reduction tests without a major decrease in catalytic activity.

One-pot, facile synthesis and fast separation of a UiO-66 composite by a metalloporphyrin using nanomagnetic materials for oxidation of olefins and allylic alcohols

One-pot facile synthesis of a new composite based on the incorporation of a metalloporphyrin within the UiO-66 metal–organic framework is reported.

Designing a New Efficient Photocatalyst Based on Functionalization of Zn-Infinite Coordination Polymer with Ru(acac)3 Complex for Dye Degradation in Aqueous Solutions: Charge Separation Effect

A new Zn-containing infinite coordination polymer, Zn-ICP, functionalized with Ru(acac)₃ complex was designed and utilized as an efficient visible light photocatalyst for dye degradation in aqueous solutions. Incorporation of Ru(acac)₃ not only extended the light absorption of the Zn-ICP to the visible region but also led to electron-hole separation. Upon visible light illumination, photoinduced electron transfer from excited state of Zn-ICP to Ru(acac)₃ occurred, resulting in electron-hole separation as indicated by photoluminescence and electrochemical impedance spectroscopy. The obtained Ru-Zn-ICP revealed enhanced visible light photocatalytic activity in degradation of organic pollutants compared to pristine Zn-ICP owing to photoinduced electron transfer in the Ru-Zn-ICP system and efficient separation of photogenerated electron-hole pairs. The prepared Ru-Zn-ICP photocatalyst was readily recycled without major loss of activity in the successive cycles.

A new water-insoluble coordination polymer as efficient dye adsorbent and olefin epoxidation catalyst

A new water-insoluble bi-metallic coordination polymer was simply prepared via polymerization-precipitation of molybdenum complex building blocks with Zn²⁺ cation. The linker was a di-carboxylic acid consisting of two coordination sites i.e. N,O and COO^- suitable for coordinating to MoO₂ unit and Zn²⁺, respectively. Characterization of the prepared coordination polymer was carried out with various physicochemical methods which confirmed the proposed structure. The prepared coordination polymer preferentially adsorbed methylene blue (more than 92% of methylene blue after 2 min) relative to methyl orange and can be reused at least four times without any loss of adsorption efficiency. The adsorption process of both dyes followed the pseudo-second order kinetic equation. Additionally, the obtained coordination polymer catalyzed epoxidation of olefins with tert-butylhydroperoxide (TBHP) quantitatively with excellent selectivity (>99%) under mild reaction conditions.