A magnetically separable ZnFe 2 O 4 Àgraphene nanocomposite photocatalyst with different graphene content was prepared by a facile one-step hydrothermal method. The graphene sheets in this nanocomposite photocatalyst are exfoliated and decorated with ZnFe 2 O 4 nanocrystals. It was found that in the presence of H 2 O 2 , the photodegradation rate of methylene blue (MB) was 88% after visible light irradiation for only 5 min and reached up to 99% after irradiation for 90 min. In comparison with pure ZnFe 2 O 4 catalyst, ZnFe 2 O 4 Àgraphene serves a dual function as the catalyst for photoelectrochemical degradation of MB and the generator of a strong oxidant hydroxyl radical ( 3 OH) via photoelectrochemical decomposition of H 2 O 2 under visible light irradiation. ZnFe 2 O 4 nanoparticles themselves have a magnetic property, which makes the ZnFe 2 O 4 Àgraphene composite magnetically separable in a suspension system, and therefore it does not require additional magnetic components as is the usual case.

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An in situ chemical synthetic approach has been designed for the fabrication of a covalently coupled hybrid consisting of graphitic carbon nitride (g-C3N4) with reduced graphene oxide (rGO) with differing g-C3N4/rGO ratio. The epoxy groups of graphene oxide (GO) undergo a nucleophilic substitution reaction with dicyandiamide (C2H4N4) to form the C2H4N4-GO composite via a covalent C-N bond, and then both the in situ polymerization of C2H4N4 and the thermal reduction of GO can be achieved at higher temperatures, forming the covalently coupled g-C3N4-rGO. FT-IR, CP-MAS NMR and XPS analyses, clearly revealed a covalent interaction between the g-C3N4 and rGO sheets. The g-C3N4-rGO exhibits an unprecedented high, stable and reversible capacity of 1525 mA h g(-1) at a current density of 100 mA g(-1) after 50 cycles. Even at a large current density of 1000 mA g(-1), a reversible capacity of 943 mA h g(-1) can still be retained. The superior electrochemical performance of g-C3N4-rGO is attributed to the specific characteristics of the unique nanostructure of g-C3N4-rGO and the concerted effects of g-C3N4 and rGO, including covalent interactions between the two moieties, the good conductivity and high special surface area of the nanocomposite, as well as the template effect of the planar amino group of g-C3N4 for the dispersed decoration of Li(+) ions.

A plausible mechanism for the reduction of p-nitrophenol catalyzed by a Pd/G catalyst in the presence of sodium borohydride.

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A straightforward strategy is designed for the fabrication of CuFe 2 O 4 -graphene heteroarchitecture via a one-step hydrothermal route to allow multifunctional properties, i.e., magnetic cycling, high photocatalytic activity under visible light irradiation, and excellent electrochemical behaviors for use as the anode in lithium-ion batteries (LIBs). Transmission electron microscopy (TEM) observations indicate that graphene sheets are exfoliated and decorated with hexagonal CuFe 2 O 4 nanoflakes. The photocatalytic activity measurements demonstrate that the combination of CuFe 2 O 4 and graphene results in a dramatic conversion of the inert CuFe 2 O 4 into a highly active catalyst for the degradation of methylene blue (MB) under visible light irradiation. CuFe 2 O 4 nanoparticles themselves have excellent magnetic properties, which makes the CuFe 2 O 4 -graphene heteroarchitecture magnetically recyclable in a suspension system. It should be pointed out that the CuFe 2 O 4 -graphene (with 25 wt % graphene) heteroarchitecture as anode material for LIBs shows a high specific reversible capacity up to 1165 mAh g −1 with good cycling stability and rate capability. The superior photocatalytic activity and electrochemical performance of the CuFe 2 O 4graphene nanocomposite can be attributed to its unique heteroarchitechture, which provides the remarkable synergistic effect between the CuFe 2 O 4 nanoflakes and the graphene sheets.

Metal-organic frameworks (MOFs) have emerged as attractive materials for energy and environmental-related applications owing to their structural, chemical and functional diversity over the last two decades. It is known that...

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