FABRICATION AND MAGNETIC INVESTIGATION OF Y OR GD CONTAINING COFE2O4 NANOCRYSTALLINE FILMS

The exertion for carrying out the substitution of Fe3+ ion in CoFe2O4 spinel by Y3+ and Gd3+ ions has been put forth in the present article. Y or Gd containing CoFe2O4 nanocrystalline films with average particl es size of 65 nm were synthesized by sol-gel method, and then the magn etic properties of the products were investigated at room temperature. To improve the crystallization of Gd-doped cobalt spinels, we buffere d them on about a 20-nm-thick CoFe2O4 thin film. However, the analysis on the results for both x-ray diffraction and magnetic measurement sh owed that it is difficult to perform the doping of Y3+ ions inside cob alt spinel ferrite. The proper doping amount of magnetic Gd3+ ion can enlarge saturation magnetization (M-s ) and coercive force (H-c)of res ultant nanocrystalline films, whereas the doping of Y only reduces the m. (C) 1998 American Institute of Physics. [S0021-8979(98)06022-8].