The enhanced anisotropic properties of the Fe3-xMxO4 (M = Fe, Co, Mn) films deposited on glass surface from aqueous solutions at low temperature

The enhancement of structural anisotropy and magnetic anisotropy in ferrite films, Fe3-xMxO4 (M = Fe, Co, Mn), which were deposited on glass substrates from aqueous solutions by thin liquid film (TLF) method at a low temperature (358 K), was compared in x-ray diffraction, conversion electron Mossbauer spectroscopy, and vibrating sample magnetometer measurements. The experimental results showed that the highly coercive Fe3-xCoxO4 films, maximum coercivity of 0.21 T at room temperature, have a preferential growing direction along the magnetic easy axis of the magnetite, <111>. While anisotropy was enhanced by the addition of Co2+ ions in the reaction solution, no enhancement was observed in the TLF-films Of Fe3O4 and Fe3-xMnxO4. The enhanced anisotropy is probably caused by the extra stabilization energy of the Co2+ ions in the octahedral sites of the spinel and the interactions between the Co2+ ions in the spinel. The alternating deposition of metal ions and oxide ions in TLF process, which is a simulation of the atomic layer deposition, may help the alignment. The most anisotropic TLF film was Fe2.59Co0.41O4.