Silver ferrite–graphene (AgFeO2‐G) as a nanocomposite photocatalyst shows potent visible‐light photocatalytic activity for the degradation of organic contaminants, and generates the strong oxidants hydroxyl radical (•OH) and superoxide anion radical (O2•−) via photoelectrochemical decomposition of H2O and O2 in the presence of air and visible light irradiation. The photogenerated electrons of AgFeO2 can transfer easily from the conduction band to the reduced graphene oxide, efficiently preventing the direct recombination of electrons and holes. As a matter of fact, AgFeO2 has a low bandgap. Furthermore, AgFeO2 nanoparticles themselves have a magnetic property, which makes them magnetically separable. The experimental results show that the graphene nanosheets in the nanocomposite catalyst are exfoliated and decorated homogeneously with AgFeO2 nanoparticles. The photodegradation occurs in a short time (ca 40 min). Also, the photocatalytic activity of the nanocomposite does not show any clear loss after ten recycles of the degradation process.

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A nanocomposite was synthesized using carbon-coated Fe 3 O 4 nanoparticle-decorated reduced graphene oxide as a convenient and efficient supporting material for grafting of a manganese-reduced Schiff base (salan) complex via covalent attachment. The nanocomposite was characterized using X-ray diffraction, Fourier transform infrared and diffuse reflectance UV-visible spectroscopies, inductively coupled plasma atomic emission spectrometry and scanning electron microscopy. It was evaluated as a catalyst for the aerobic epoxidation of olefins in acetonitrile in combination with a sacrificial co-reductant (isobutyraldehyde). The catalytic performance of the heterogeneous system of the Mn-salan complex is superior to that of the homogeneous one. The catalyst activity strongly depends on the reaction temperature and nature of the solvent. The epoxide yield increases with the nucleophilic character of the olefin. The nanocomposite performs well as an epoxidation catalyst for electron-rich and conjugated olefins. It can be recovered from the reaction medium by magnetic decantation and reused, maintaining good catalytic activity.

A new composite was synthesized by grafting the (1R,2S)-1-(N-salicylideneamino)-2-indanol complex of Mn onto graphene oxide/Fe3O4@C. It catalysed the aerobic epoxidation of olefins with a selectivity of >98% and enantioselectivity of >99%.

A hydrazone Schiff base ligand derived from salicylaldehyde and benzhydrazide has been synthesized and reacted with vanadium(IV) leading to the corresponding vanadium(V) complex. The complex has been anchored on the surface of functionalized silica gel by N,O-coordination to the covalently Si-O bound modified salicylaldiminato ligand. The supported complex has been evaluated as a catalyst for hydrocarbon oxidation with hydrogen peroxide in acetonitrile. The heterogeneous system proved to be an efficient catalyst and was able to activate hydrogen peroxide toward the oxidation of alkenes, alkanes, benzene, and alkylaromatic compounds with more than 2,500 h -1 activity.

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