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Poly(vinyl alcohol) (PVA) composites with incorporation of Ag nanoparticle–reduced graphene oxide (Ag–rGO) hybrids as fillers were prepared and the thermal conductivity of the resulting Ag–rGO/PVA composites was investigated. Ag–rGO hybrids were fabricated by a chemical reduction method, and their morphology, crystal, and chemistry were characterized. Benefiting from the unique characteristic of Ag–rGO hybrids, the Ag–rGO/PVA composites showed a 153% increase in thermal conductivity with addition of 1.0 vol% Ag–rGO, which was much superior to the composites with bare rGO. The significant thermal conductivity enhancement was probably attributed to the combined factors of homogeneous filler dispersion, enhanced interfacial interaction, and “bridge” effect of Ag NPs for establishing thermally conductive networks. Therefore, our study shows that the Ag–rGO hybrids have the potential to be successfully used as the nanofillers of polymer composites for thermal management applications.

Here we represented the heteropoly acids (HPAs) and polyoxometalate (POM)‐based ionic liquids (ILs) catalyzed the effective alcoholysis of furfural alcohol (FAL) to alkyl levulinate. H5AlW12O40 exhibited the highest catalytic activity among HPAs, furnishing > 99 % FAL conversion and 80 % yield of butyl levulinate (BL). The incorporation of IL framework containing sulfate group into HPAs resulted in the enhanced catalytic performance. [MIMBS]5[AlW12O40] achieved the highest BL yield of 94 % and maintained a good catalytic activity after 6 times of recycle and reuse experiments. The effect of the Hammett acidity and structure of catalyst on the catalytic performance of HPAs and POM‐based ILs was also investigated.

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Nine novel coordination polymers, namely, ijZnLIJbpmp) 0.5 ]·3H 2 O (1), ijZn 2 L 2 IJbibp) 2 ]·H 2 O (2), ijZnLIJbpp)]·7H 2 O (3), ijZn 2 L 2 IJbidpe) 2 ]·2H 2 O (4), ijZn 3 L 3 IJbpmp) 0.5 ·IJH 2 O) 2 ] (5), ijZnLIJbibpip) 2 ]·3H 2 O (6), ijZnLIJbpmb)] (7), ijZnLIJbib)] ·DMF·4H 2 O (8) and ijZnLIJbibp)]·2DMF (9) [H 2 L = 4,4′-IJphenylazanediyl)dibenzoic acid, bpmp = 1,4-bisIJ4-pyridinylmethyl)piperazine, bibp = 4,4′-bisIJimidazol-1-yl)biphenyl, bpp = 1,3-bisIJ4-pyridyl)propane, bidpe = 4,4′-bisIJimidazol-1-yl)diphenyl ether, bibpip = 1,4-bisIJ4-IJ1H-imidazol-l-yl)benzyl)piperazine, bpmb = 1,4-bisIJpyridin-4-ylmethoxy)benzene and bib = 1,4-bisIJimidazolyl)butane], have been synthesized under solvothermal and hydrothermal conditions. Their structures have been characterized by single-crystal X-ray diffraction analysis, elemental analysis, infrared spectroscopy and thermogravimetric analysis. Compound 1 exhibits an infinite 3D structure with a {4 4 ·6 10 ·8} topology. Compound 2 features an unusual two-fold interpenetrating 3D framework with a {3 19 ·4 17 ·5 9 } topology. Compound 3 shows interweaving helical chains. Compound 4 exhibits 2-fold 1D chains mutually interpenetrating each other forming 2D sheets. Compound 5 exhibits an unusual 2D wave-like sheet. Compound 6 shows a 5-fold interpenetrating framework.Compound 7 displays a 1D chain. Compound 8 also has a (4,4) layer structure which can be split into interesting helixes. Compound 9 shows three-fold interpenetrating sheets which are stacked in an ABAB fashion and form a 3D framework. Their photochemical properties were also measured.