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The catalyst (N,N-bis(2,6-dibenzhydryl-4-ethoxyphenyl)butane-2,3-diimine)nickel dibromide, a late transition metal catalyst, was prepared and used in ethylene polymerization. The effects of reaction parameters such as polymerization temperature, co-catalyst to catalyst molar ratio and monomer pressure on the polymerization were investigated. The α-diimine nickel-based catalyst was demonstrated to be thermally robust at a temperature as high as 90 °C. The highest activity of the catalyst (494 kg polyethylene (mol cat)⁻¹ h⁻¹) was obtained at [Al]/[Ni] = 600:1, temperature of 90 °C and pressure of 5 bar. In addition, the performance of a binary catalyst using nickel- and palladium-based complexes was compared with that of the corresponding individual catalytic systems in ethylene polymerization. In a study of the catalyst systems, the average molecular weight and molecular weight distribution for the binary polymerization were between those for the individual catalytic polymerizations; however, the binary catalyst activity was lower than that of the two individual ones. The obtained polyethylenes had high molecular weights in the region of 10⁵ g mol⁻¹. Gel permeation chromatography analysis showed a narrow molecular weight distribution of 1.44 for the nickel-based catalyst and 1.61 for the binary catalyst system. The branching density of the polyethylenes generated using the binary catalytic system (30 branches/1000 C) was lower than that generated using the nickel-based catalyst (51/1000 C). X-ray diffraction study of the polymer chains showed higher crystallinity with lower branching of the polymer obtained. Also Fourier transform infrared spectra confirmed that all obtained polymers were low-density polyethylene.

A benzhydryl-derived ligand framework and the corresponding nickel(II) α-diimine complex were synthesized, characterized and the complex used in ethylene polymerization. High thermal stability of the complex was a significant aspect. The performance of a binary catalyst system involving nickel and palladium complexes in polymerization was compared with that of corresponding single catalysts. The branching of polyethylene obtained in the presence of the binary catalyst was lower compared to corresponding individual catalytic systems.

Polymer-dominated membranes with switchable wettability are highly desired due to their on-demand applications for oil/water separation. Herein, a low-cost methodology to fabricate membranes consisting of hyperbranched polyurethane (HBPU) and fluorine-modified silica (F-SiO₂) with tunable wettability by electrospinning is reported. The HBPU/F-SiO₂ composite membranes can be transformed from superhydrophobicity to -philicity through plasma treatment; these membranes exhibit different wettability for effective separation of surfactant-stabilized water-in-oil and oil-in-water emulsions.

Creating divisions: Membranes composed of hyperbranched polyurethane (HBPU) and fluorine-modified silica (F-SiO₂) with tunable wettability can be prepared through electrospinning. These membranes can be transformed from superhydrophobicity to -philicity through plasma treatment and used for the effective separation of surfactant-stabilized water-in-oil and oil-in-water emulsions (see figure).

A significant synergic effect between a metal–organic framework (MOF) and Fe₂SO₄, the so-called MOF⁺ technique, is exploited for the first time to remove toxic chromate from aqueous solutions. The results show that relative to the pristine MOF samples (no detectable chromate removal), the MOF⁺ method enables super performance, giving a 796 Cr mg g⁻¹ adsorption capacity. The value is almost eight-fold higher than the best value of established MOF adsorbents, and the highest value of all reported porous adsorbents for such use. The adsorption mechanism, unlike the anion-exchange process that dominates chromate removal in all other MOF adsorbents, as unveiled by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), is due to the surface formation of Fe_0.75Cr_0.25(OH)₃ nanospheres on the MOF samples.

A pause from pores: Relying on the surface rather than the pores of metal–organic frameworks (MOFs), the MOF⁺ method enables an ultrahigh chromate removal in aqueous solution of up to 796 Cr mg g⁻¹, exceeding any porous material for this kind use. The hexavalent chromate is reduced by FeSO₄ to generate Fe^III and Cr^III ions, the MOF surface then induces the formation of Fe_0.75Cr_0.25(OH)₃ nanospheres.

Semiconductor-based photocatalysis is an environmental friendly and cost-effective technique for water treatment. Due to their unique properties, metal–organic frameworks (MOFs) are considered as ideal platform to develop composite photocatalyst. In this study, Bismuth oxychloride (BiOCl) was first attempt to be incorporated with highly stable MOFs, UiO-66(Zr) by hydrothermal reaction. Different characterization methods including X-ray diffraction, Scanning electron microscopy, Fourier transform infrared spectroscope, X-ray photoelectron spectroscopy had been used to prove the successful synthesis of composite photocatalyst. The resultant BiOCl/UiO-66 composite showed higher photodegradation performance of Rhodamine B (RhB) under ultraviolet and visible light irradiation than that of pristine materials and their mechanically mixed sample. In addition, the composite exhibited good structural stability and reusability. The photocatalytic mechanism of RhB degradation over the composite under visible light proceeded via a photosensitization process. A better adsorptivity of RhB and effective electron transfer within the hybrid material might be responsible for the enhanced photocatalytic performance.

BiOCl and UiO-66(Zr) were combined together through chemical bonds (C-Cl), and a different morphology compared to pristine material was obtained in the preparation process, which brought a better adsorptivity of RhB and effective electron transfer within the hybrid material. The BiOCl/UiO-66(Zr) composite shows prior photosensitization degradation performance for RhB under visible light than pristine materials.

Membrane materials with excellent selectivity and high permeability are crucial to efficient membrane gas separation. Microporous organic materials have evolved as an alternative candidate for fabricating membranes due to their inherent attributes, such as permanent porosity, high surface area, and good processability. Herein, a unique pore-chemistry concept for the designed synthesis of microporous organic membranes, with an emphasis on the relationship between pore structures and membrane performances, is introduced. The latest advances in microporous organic materials for potential membrane application in gas separation of H₂, CO₂, O₂, and other industrially relevant gases are summarized. Representative examples of the recent progress in highly selective and permeable membranes are highlighted with some fundamental analyses from pore characteristics, followed by a brief perspective on future research directions.

Recent advances regarding microporous organic materials for membrane gas separation are reviewed. Critical challenges associated with the designed synthesis of membrane materials with defined porous structures, and the correlations between pore chemistry and membrane separation performance, in terms of selectivity and permeability, are discussed.

Antireflection surfaces and coatings have attracted considerable interests because they can maximize light transmittance of the substrates. In this work, zeolite antireflective (ZAR) coatings are prepared via layer-by-layer (LBL) assembly of MFI-type zeolite silicalite-1 and polyelectrolyte. A micro- and macroporous hierarchical structure was obtained which contributes to the antireflective property of the zeolite coatings. The light transmittance of the coating on quartz can achieve as high as 99.3% at 650 nm. Furthermore, a superhydrophobic ZAR coating can be obtained by chemical modification with 1H,1H,2H,2H–perfluorooctyl-triethoxysilane. This work demonstrates that zeolites are excellent candidates as high transparent superhydrophobic coatings.

Zeolite antireflective (ZAR) coatings have been successfully prepared by LBL assembly method with silicalite-1 nano-crystals and polyelectrolyte, followed by calcination to eliminate the organic component. A superhydrophobic ZAR coating can be obtained by chemical modification. The present work demonstrates that zeolites are excellent materials for highly transparent superhydrophobic coatings.