Abstract
In this study, the effects of NaOH and precursor concentration on the particle size and magnetic properties of FeCo nanoparticles are investigated. Results suggest that an optimized ratio of NaOH molar concentration [OH] to precursor molar concentration [M] is required to obtain a small particle size, high saturation magnetization, and low coercivity. When the [OH]/[M] ratio was greater than 40, the FeCo nanoparticles aggregated, whereas when the [OH]/[M] ratio was less than 20, FeCo + CoFe2O4 nanoparticles were obtained due to unstable reduction reactions. When [OH]/[M] was 40, the 387 nm FeCo nanoparticles showed the highest saturation magnetization and lowest coercivity, which are the best conditions for achieving high permeability. In contrast, the complex permeability of the 173 nm FeCo nanoparticles was higher than that of the 387 nm FeCo nanoparticles owing to the decrease in the demagnetization effect in the high frequency band. This confirmed that the particle size had a greater effect on the complex permeability than that on the saturation magnetization and coercivity in GHz ranges.
Highlights
With the introduction of fifth-generation (5G) telecommunication and electronic devices, frequency band utilization has increased significantly; electromagnetic wave (EMW) absorption materials for the broadband range are required to eliminate electromagnetic wave interference (EMI)
When using metallic magnetic particles for the high frequency band, the complex permeability decreases owing to the eddy current effect; it is necessary to reduce the eddy current effect by reducing the size and morphology of the particles
We determined the optimized conditions of NaOH and precursor concentration to obtain good magnetic properties and small particles; we investigated the relationship between the particle size and magnetic properties
Summary
With the introduction of fifth-generation (5G) telecommunication and electronic devices, frequency band utilization has increased significantly; electromagnetic wave (EMW) absorption materials for the broadband range are required to eliminate electromagnetic wave interference (EMI). Magnetic materials require high complex permeability for the high attenuation performance of EMW absorption materials. Metallic magnetic materials have attracted considerable attention owing to their high Sneok’s limit and complex permeability compared to those of ferrites, such as CoFe2O4,2 Fe3O4,3 and NiFe2O4.4 Among bi-alloy magnetic materials, FeCo nanoparticles have shown high saturation magnetization, high Curie temperatures, low coercivity, and high complex permeability in a wide frequency range. When using metallic magnetic particles for the high frequency band, the complex permeability decreases owing to the eddy current effect; it is necessary to reduce the eddy current effect by reducing the size and morphology of the particles.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
