A multi-layer core-shell structure CoFe₂O₄@Fe₃C@NiO composite with high broadband electromagnetic wave-absorption...

Area of Science:

• Materials Science
• Nanotechnology
• Electromagnetics

Background:

• Achieving enhanced electromagnetic wave absorption and broader absorption bands is crucial for developing advanced absorbing materials.
• Composite materials and core-shell structures are effective strategies for broadband absorption and enhanced capabilities.

Purpose of the Study:

• To synthesize and characterize novel core-shell nanocomposite metal-organic framework (MOF) derivatives for electromagnetic wave absorption.
• To investigate the electromagnetic wave absorption properties of CoFe2O3@C (double core-shell) and CoFe2O4@Fe3C@NiO (three-layered core-shell) structures.

Main Methods:

• Preparation of nanocomposite MOF derivatives CoFe2O3@C and CoFe2O4@Fe3C@NiO using chemical compound methods.
• Evaluation of electromagnetic wave absorption performance, including reflection loss (RL) and effective absorption band (EAB).

Main Results:

• The multi-layer core-shell structures provide increased active sites, promoting multiple reflections and scattering of electromagnetic waves for improved attenuation.
• CoFe2O3@C exhibited a minimum reflection loss (RLmin) of -52.7 dB at 13.3 GHz with a 2.04 mm thickness and an EAB of 9.35 GHz.
• CoFe2O4@Fe3C@NiO achieved an EAB of 11.9 GHz at a matched thickness of 2.2 mm.
• Both synthesized materials demonstrated a twofold increase in EAB compared to the ZIF-67 derivative with a minimal thickness increase.

Conclusions:

• The developed multi-layer core-shell nanocomposites offer superior electromagnetic wave absorption capabilities.
• These advanced materials show significant potential for applications requiring efficient and broadband electromagnetic wave absorption.