The sol-gel method was used to prepare three kinds of nanometer magnetic particles,such as the nano-cobalt ferrite oxide powders and those doped by LaCl3·nH2O. In the thermo-decomposition process of the precursor...The sol-gel method was used to prepare three kinds of nanometer magnetic particles,such as the nano-cobalt ferrite oxide powders and those doped by LaCl3·nH2O. In the thermo-decomposition process of the precursors to get these magnetic particles,TG/DTG was applied to investigate their character. The prepared magnetic particles with average diameter less than 100 nm were characterized by XRD and TEM. The results show the difference between the activation energies of these particles in different thermo-decomposition stages,even not in the same stage for different samples. The cobalt ferrite doped with La3+ affects its saturation magnetization(ms) and coercive force(Hc). As CoCl2·6H2O is partly substituted by La3+,the value of Hc decrease with the increase of ms. When FeCl2·4H2O is partly substituted by La3+,Hc increases obviously. The three kinds of nanometer magnetic particles were doped into polyethylene glycol-20000(peg-20000) with different ratios respectively to obtain compound substance with optimal conductivity of 0.686 S/m.展开更多
基金Project (50374077) supported by the National Science Foundation of ChinaProject (07D069) supported by the Education Department Foundation of Hunan Province, China
文摘The sol-gel method was used to prepare three kinds of nanometer magnetic particles,such as the nano-cobalt ferrite oxide powders and those doped by LaCl3·nH2O. In the thermo-decomposition process of the precursors to get these magnetic particles,TG/DTG was applied to investigate their character. The prepared magnetic particles with average diameter less than 100 nm were characterized by XRD and TEM. The results show the difference between the activation energies of these particles in different thermo-decomposition stages,even not in the same stage for different samples. The cobalt ferrite doped with La3+ affects its saturation magnetization(ms) and coercive force(Hc). As CoCl2·6H2O is partly substituted by La3+,the value of Hc decrease with the increase of ms. When FeCl2·4H2O is partly substituted by La3+,Hc increases obviously. The three kinds of nanometer magnetic particles were doped into polyethylene glycol-20000(peg-20000) with different ratios respectively to obtain compound substance with optimal conductivity of 0.686 S/m.
