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Synthesis of a composite mesoporous iron−titanium oxide by ultrasound irradiation is here reported. Iron(III) ethoxide and titanium(IV) isopropoxide were used as precursors, and dodecylamine was used as the templating agent. The synthesis was completed in 6 h in one stage. The product was characterized by XRD, TEM, DSC, TGA, XPS, EDX, and BET methods. Magnetic properties were studied by magnetization and Mössbauer spectroscopy. Short-range ordered structure of the product was demonstrated by low-angle XRD measurements. After heat treatment, this structure collapsed and crystalline phases of γ-Fe2O3 oxide and anatase of TiO2 were observed. The calcinated material showed slight magnetic properties corresponding to the amount of iron oxide. The removal of the surfactant by extraction with diluted nitric acid resulted in the increase of surface area to 650 m2/g and the pore volume to 0.45 mL/g. The catalytic properties of the material were examined in the oxidation of cyclohexane under mild conditions, and a high conversion of the substrate to cyclohexanol and cyclohexanone was obtained.

This paper describes, for the first time, a simple sonochemical method for the synthesis of nanoparticles of a series of rare earth orthoferrites. This sonochemical process is enabling synthesis of nanoparticles of the rare earth orthoferrites at a substantially lower calcination temperature by using simple precursors, iron pentacarbonyl and rare earth carbonates. It is particularly noteworthy that the cogeneration of the garnet phase has not been observed, as is usual with the conventional methods. The drastic reduction in the calcination temperature could be due to the ultrasonic generation of amorphous iron oxide from Fe(CO)5. Nanosized GdFeO3, ErFeO3, TbFeO3, and EuFeO3 were prepared by this method and their magnetic properties were also studied in detail.

This paper reports on the inorganic sonochemical synthesis of crystalline Ni(C4H6N2)6(PF6)2, Fe(C4H6N2)6(BF4)2, and Ni(C4H6N2)6(BF4)2 in the ionic liquids, 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMI)+(PF6)– and 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMI)+(BF4)–. The structures of the compounds were determined and refined by using powder X‐ray diffraction methods. The salts crystallize in the trigonal P$\tilde {3}$ space group. IR, Raman and 19F NMR spectroscopic studies confirm that the PF6– and BF4– anions are not bonded to the metal cations. Magnetic measurements reveal the paramagnetic nature of the complexes. Mössbauer investigations show that the iron atom in Fe(C4H6N2)6(BF4)2 is in the oxidation +2 state. The broad EPR signals, which reflect the octahedral symmetry of the nickel complexes, were measured for Ni(C4H6N2)6(PF6)2 and Ni(C4H6N2)6(BF4)2. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)