Mechanochemical Synthesis and Characterization of Nanocrystalline Copper-Cobalt Ferrites

来源 :Acta Metallurgica Sinica(English Letters) | 被引量 : 0次 | 上传用户:qq243129435
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Nanocrystalline copper-cobalt ferrites with composition Cu_(1-x)Co_xFe_2O_4,where x = 0.2 and 0.8,were synthesized by mechanochemical treatment of co-precipitated precursors.The ferrite powders were characterized by XRD and Mossbauer spectroscopy.Results proved obtaining of spinel ferrites with crystallite size smaller than 10 nm.Increasing of crystallite size of samples with increasing of mechanochemical treatment duration was established,too.Catalytic properties of obtained ferrites were tested in reactions of oxidation of CO,methanol and dimethyl ether.High catalytic activity of nanocrystalline copper-cobalt ferrites toward CO and CH_3OH(about 100% conversions of CO and CH_3OH at 160 ℃)and moderate activity toward(CH_3)_2O oxidation were established.The results obtained revealed that the Co/Cu atomic ratio is an important factor determinant the behavior of catalysts toward methanol and DME oxidation. Nanocrystalline copper-cobalt ferrites with composition Cu_ (1-x) Co_xFe_2O_4, where x = 0.2 and 0.8, were synthesized by mechanochemical treatment of co-precipitated precursors. The ferrite powders were characterized by XRD and Mossbauer spectroscopy. Residues of research obtained obtain spinel ferrites with crystallite size smaller than 10 nm. Increasing of crystallite size of samples with increasing of mechanochemical treatment duration was established, too. Catalytic properties of obtained ferrites were tested in reactions of oxidation of CO, methanol and dimethyl ether. High catalytic activity of nanocrystalline copper -cobalt ferrites toward CO and CH_3OH (about 100% conversions of CO and CH_3OH at 160 ° C) and moderate activity toward (CH_3) __2O oxidation were established. The results gave revealed that the Co / Cu atomic ratio is an important factor determinant the behavior of catalysts toward methanol and DME oxidation.
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