Sustainable microfibrillated cellulose (MFC) aerogels are considered to be good templates for the growth of functional organic or inorganic nanoparticles. In this work, MFC aerogels with high porosity (99.9%) and low density (2.91 mg/cm 3 ) were produced by freeze-drying. Then the obtained MFC aerogels were used as templates for the synthesis of MFC/polypyrrole (PPy)/silver nanoparticles (Ag) hybrid aerogels by a simple dip-coating method. Our results demonstrated that the obtained hybrid aerogels maintained the attractive features of the pristine MFC aerogels, such as high porosity, low density, and high compressive stress, during the preparation process. Compared with MFC aerogels and MFC/ PPy hybrid aerogels, the MFC/PPy/Ag hybrid aerogels exhibited enhanced antimicrobial and electrical conductive properties due to the combination of PPy and Ag. Moreover, the electrical conductivity and compressible properties of the MFC/PPy/Ag hybrid aerogels led to their pressure responsive property. These features make the hybrid aerogels promising candidates for wound healing, energy storage, and pressure sensing applications.

A novel chelating resin, polyacrylonitrile-2-aminothiazole (PAN-AT), was synthesized simply by the reaction of polyacrylonitrile with 2-aminothiazole. Optimization of the PAN-AT synthesis was carried out at different temperatures, different molar ratios of reagents, and different time intervals in N,N-dimethylformamide (DMF) using response surface methodology (RSM) for the first attempt. The functional group capacity (the content of the functional group) and the percentage conversion of the functional group of PAN-AT prepared under the optimum conditions were 3.94 mmol/g and 41.10%, respectively. The structure of PAN-AT was characterized by elemental analysis and FTIR. Meanwhile, the adsorption properties of the resin for Hg(II) were investigated by batch and column experiments. The results suggested that the resin possessed much better adsorption capability for Hg(II) than for other metal ions and the maximum saturated adsorption capacity estimated from the Langmuir model was 454.9 mg/g at 308 K. Furthermore, the resin could be regenerated through the desorption of the Hg(II) anions using 3.0 mol/L HNO3 solution and could be reused to adsorb again. Finally, the resin and its metal complexes were studied by SEM, TGA, and energy dispersive X-ray spectroscopy (EDS). Also, the PAN-AT chelating resin could provide a potential application for a treatment process of Hg(II) contaminated wastewater.

The first example of oxidant-free cobalt-catalyzed synthesis of five-membered spirocycles is reported from benzimidates and maleimides utilizing nitrobenzene as promoter. In contrast to previously known cobalt-catalyzed oxidative C-H functionalization reactions, this transformation occurs efficiently in the absence of oxidant and is accompanied by liberation of hydrogen. The spiro-lactams were readily achieved by the hydrolysis of as-prepared spirocyclic compounds. The Cp*Rh(III) catalyst shows poor reactivity.

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As a kind of excellent diesel-blending component, polyoxymethylene dimethyl ethers (PODEn) have received widespread attention. Herein, Al-SBA-15 molecular sieves with different Si/Al ratios and pore sizes were synthesized and used to investigate the catalytic performance for the synthesis of polyoxymethylene dimethyl ethers from methylal and trioxane. X-ray diffraction, N 2 adsorption−desorption, scanning electron microscopy, transmission electron microscopy, X-ray fluorescence, and 27 Al NMR were used to characterize the structures of obtained catalysts. Ammonia temperature-programmed desorption and pyridine adsorption were carried out to investigate the acid properties of the catalysts. Through comparison of the catalysts with different Al contents, it was found that the relatively weak acid was more suitable for the synthesis of PODEn than the relatively strong acid in the catalytic system of Al-SBA-15. On the Al-SBA-15(2)-150 catalyst, which has only a weak acid of 0.163 mmol/g, the highest TOX conversion rate and highest PODEn yield and selectivity were achieved, showing the best catalytic performance. It appears that the PODEn synthesis can be catalyzed by not only a Bronsted acid but also a Lewis acid. The catalysts with strong acid and/or with a large number of acids will cause the generation of significant amount of methyl formate byproduct. Through comparison of the catalysts with different pore sizes, it was found that a relative larger pore size of the catalyst was beneficial for the PODEn synthesis to a certain extent under the catalysts with strong acid and/or large acid amount, but on the catalyst that had only weak acid and a relatively lesser amount, the change of pore size had almost no effect on the yield and selectivity of PODEn products.

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The mechanisms and origins for the Pd- and Ni-catalyzed regioselective hydrosilylation of allene have been investigated by means of density functional theory (DFT) calculations. The free-energy profiles of Pd- and Ni-catalyzed reactions with small and bulky N-heterocyclic carbene (NHC) ligands are calculated to determine the mechanism for regioselectivities. The calculation results show that different metals (Ni vs Pd) lead to regiochemical reversals for the hydrosilylation of allene. The allylsilane is the major product via palladium catalysis with small NHC ligand, while the vinylsilane is the major product via nickel catalysis with bulky NHC ligand. Both electronic and steric factors play a key role in the regioselectivities for the hydrosilylation of allene via Pd and Ni catalysts. The calculation results are in good agreement with observed regioselectivities and could provide insights into the design of new catalysts for the regioselectivity of hydrosilylation reactions.

By taking advantage of cellulose, graphene oxide (GO), and the process for crosslinking using epichlorohydrin (ECH), we propose a simple and novel method to prepare GO/cellulose hydrogel with good potential to adsorb metal ions. GO nanosheets containing carboxyl and hydroxyl groups were introduced into the surface of the cellulose hydrogel with retention of the gel structure and its nanoporous property. Due to the introduction of GO, the GO/cellulose composite hydrogels exhibited good compressive strength. Adsorption capacity of Cu2+ significantly increases with an increase in the GO/cellulose ratio and GO/cellulose hydrogel showed high adsorption rates. The calculated adsorption capacities at equilibrium (qnormalecal) for GO/cellulose hydrogel (GO:cellulose = 20:100 in weight) was up to 94.34 mg·g−1, which was much higher than that of the pristine cellulose hydrogels. Furthermore, GO/cellulose hydrogel exhibited high efficient regeneration and metal ion recovery, and high adsorption capacity for Zn2+, Fe3+, and Pb2+.