Preparation and microwave absorption properties of Ni-B alloy-coated Fe₃O₄ particles

The Fe₃O₄ particles that were activated with Pd-Sn catalytic nuclei by single-step activation were used as cores for obtaining nickel- and boron-decorated particles with shell/core structure via electroless plating. The materials were characterized by TEM, SEM, EDX, X-ray diffraction, VSM and microwave network analyzer. The results showed that Fe₃O₄ particles coated with Ni-B alloy films had reduced metal deposition in the reaction solution. There was no peak of amorphous alloy Ni-B by XRD but the inverse spinal Fe₃O₄. The calculated results indicate that the Fe₃O₄ densely coated with Ni-B exhibits better absorption performance than the pure Fe₃O₄ in the range of 2-18 GHz, such as more powerful absorbing capability and a wider electromagnetic wave absorbing frequency band.