NiCuZn ferrite flakes prepared using a sol–gel bubble method and its magnetic properties

Ni0.23Cu0.11Zn0.66Fe2O4 ferrite flakes, with thickness of about 8 μm and average diameter of 20–35 μm, were prepared using a sol–gel bubble method. Morphology, phase evolution, static and dynamic magnetic properties of the flakes and their composites were studied. Magnetic measurements showed that easy magnetization direction of the flaky filler composite was parallel to its sample plane. Composites made of silicone resins and flakes had higher complex permeability, which can be attributed to the reduction in demagnetization factor due to their flaky shapes. This sol–gel bubble method should be also applicable to fabricating flakes of other multi-component oxides.

Research highlights▶ Ni0.23Cu0.11Zn0.66Fe2O4 ferrite flakes were successfully prepared using a sol-gel bubble method. ▶ Using these flakes as filler in the silicon resin composite, the aligned flaky filler composite had hysteresis loops dependent on their orientations to the applied magnetic field (H). ▶ And it also had greatly increased complex permeability, as compared to the composite with usual irregular filler. ▶ This sol-gel bubble method should be applicable to the preparation of other multi-component oxide flakes.