INFLUENCE OF SILICON DOPING ON THE STRUCT URE AND THE MAGNETIC PROPERTY OF GAMMA-FE2O3 PARTICLE

The structure of Si-doped gamma-Fe2O3 small particles prepared by dopi ng with different silicon content has been investigated by X-ray diffr action based on Furuhashi method. The results show that the lattice pa rameters decrease continuously with increasing silicon content, which suggests an evidence of a solid solution for Si-doped gamma-Fe2O3. The Si4+ cation in the like-spinels appears a strong tendency to distribu tion in the tetrahedral site. The oxygen parameter as well as the mean size of interstices of tetrahedral and octahedral also appears a cert ain influence of silicon doping. Additionally, grain sizes and lattice distortions of the samples which were calculated following the Stokes and Wilson formula indicate a significant decrease for the grain size with increasing silicon content and a little change for the lattice d istortion. Finally, the coercivity and saturation magnetization of the Si-doped gamma-Fe2O3 particles are discussed.