Microwave absorption properties of FCC-Co/Al2O3 and FCC-Co/Y2O3 nanocapsules

FCC-Co/Al2O3 and FCC-Co/Y2O3 nanocapsules were prepared by a modified arc-discharge technique, which exhibited the maximum magnetic resonance (μ″μ″) peak at the same frequency of 6.4 GHz. For the FCC-Co/Al2O3 nanocapsules, the reflection loss being less than −20 dB was obtained in the frequency range of 9.6–11 GHz with an absorber thickness of 4–5 mm, while a minimum reflection loss of −29.7 dB was achieved at 10 GHz with an absorber thickness of 5 mm. The FCC-Co/Y2O3 nanocapsules are with broader frequency range (9.7–12.4 GHz) and thinner matching thickness (2–4 mm) for RL<−20 dB, due to comparatively higher magnetization. The FCC-Co/Al2O3 and FCC-Co/Y2O3 nanocapsules may become attractive candidates for a new type of electromagnetic wave absorptive materials.