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Due to the rapid development of modern industry, oily wastewater, which contained poisonous chemicals, would cause damage to marine fishery resources, and finally threaten human health. To address this issue, we herein report a fibrous membrane for oil-water separation. Firstly, the silicone polymer was synthesized by the in situ polymerization of aminopropyl trimethoxysilane and 3-glycidyloxypropyl trimethoxysilane in a polycaprolactone (PCL) solution. Then, the silicone decorated PCL (S-PCL) fibrous membranes were then prepared via electrospinning the synthesized solution. The decorated silicone offers a good porous structure for fibrous membranes. Specifically, the decorated silicone endows the PCL fibrous membrane with a good lipophilic/hydrophobic performance with a water contact angle of 169° under oil. More importantly, the obtained fibrous membrane owned a good oil-water selectivity. The oil droplets could be spread and absorbed by the fibrous membrane in water within 5 s. Such efficient separation for oil and water mixtures, endowed by silicone, will make the PCL fibrous membrane an environmental-friendly candidate for treating oily wastewater. [ABSTRACT FROM AUTHOR]

Novel hierarchical CuS/ZnS hetero-nanowires were designed and successfully synthesized through a template-free and surfactant-free chemical solution method with a mixed solvent of dimethyl sulfoxide and ethylene glycol. The precursors of CuS and the molar ratio of Cu:Zn, play a crucial role in controlling the morphology of the CuS/ZnS heterostructure. The precursors of CuS serve both as a source material for chemical transformation to CuS and as sacrificial templates for the growth of ZnS nanosheets by adding zinc(ii) ions, finally forming a ZnS/CuS hierarchical nanomaterial with p-n heterojunctions. The as-prepared samples were examined by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, UV-visible diffuse reflectance spectroscopy and Brunauer-Emmett-Teller measurements. Photocatalytic activities for methylene blue and rhodamine B were investigated under visible-light irradiation, and appreciably increased photocatalytic activity compared to individual counterparts is achieved by the hierarchical CuS/ZnS hetero-nanowires. The p-n heterojunction, one-dimensional nanostructures and large specific surface area are responsible for the improved photocatalytic activities.

Development of efficient and easy‐to‐prepare low‐cost oxygen reaction electrocatalysts is essential for widespread application of rechargeable Zn‐air batteries (ZABs). Herein, we mixed NaCl and ZIF‐8 by simple physical milling and pyrolysis to obtain a metal‐free porous electrocatalyst doped with Cl (mf‐pClNC). The mf‐pClNC electrocatalyst exhibits a good oxygen reduction reaction (ORR) activity (E1/2=0.91 V vs. RHE) and high stability in alkaline electrolyte, exceeding most of the reported transition metal carbon‐based electrocatalysts and being comparable to commercial Pt/C electrocatalysts. Likewise, the mf‐pClNC electrocatalyst also shows state‐of‐the‐art ORR activity and stability in acidic electrolyte. From experimental and theoretical calculations, the better ORR activity is most likely originated from the fact that the introduced Cl promotes the increase of sp3‐hybridized carbon, while the sp3‐hybridized carbon and Cl together modify the electronic structure of the N‐adjacent carbons, as the active sites, while NaCl molten‐salt etching provides abundant paths for the transport of electrons/protons. Furthermore, the liquid rechargeable ZAB using the mf‐pClNC electrocatalyst as the cathode shows a fulfilling performance with a peak power density of 276.88 mW cm−2. Flexible quasi‐solid‐state rechargeable ZAB constructed with the mf‐pClNC electrocatalyst as the cathode exhibits an exciting performance both at low, high and room temperatures. [ABSTRACT FROM AUTHOR]

N-Alkylation of alcohols by hydrogen transfer is a green and atomically economical method for the preparation of amines; however, most of the reported catalysts are noble metal and homogeneous catalysts. Essentially, heterogeneous catalysts with the stable co-existence of multiple valence metals are difficult to prepare. In this study, we designed mixed-metal oxide (MMO) CuMn2O4 with a self-supported mesoporous structure as a catalyst for the reactions of substituted alcohols and benzenesulfonamides/anilines. It possessed a high catalytic activity in the hydrogen transfer reaction, which can be mainly attributed to the Jahn–Teller effect and the unique electronic states of copper and manganese ions for their variable values and complex coordination status in the MMO material. Furthermore, the self-supported CuMn2O4 catalyst with the advantages of high surface area and large particle size, benefitted the adsorption–desorption of hydrogen over active sites, which established a 30% higher yield in the N-alkylation reaction as compared with its bulk alternative. Therefore, the active compositions with variable values and the unique mesoporous structure of CuMn2O4 were the combined reasons for the efficient hydrogen transfer and further N-alkylation reaction. Extensive substrates, such as, sulfonamides and alcohols, including electron-donating and electron-withdrawing substituents on benzyl alcohols and benzene sulfonamides were tried and were well-tolerated to achieve high yields, suggesting that the self-supported CuMn2O4 possesses excellent catalytic activity and broad universality. [ABSTRACT FROM AUTHOR]