Coconut shell waste encased MnFe2O4 for enhanced microwave absorption

• Published in: Journal of alloys and compounds 2024-10, Vol.1002, p.175116, Article 175116
• Main Authors: Ashfaq, Aamna, Ashfaq, M. Zeeshan, Cheng, Xingxing, Gong, Hongyu, Saleem, Adil, Iqbal, Rashid
• Format: Article
• Language: English
• Subjects: Activated carbon; Dielectric loss; Effective absorption bandwidth; Hybrid composite; Interfacial polarization; Waste material
• ISSN: 0925-8388
• DOI: 10.1016/j.jallcom.2024.175116

Radar systems, communication tools, and stealth technologies are just a few of the many areas that can benefit from microwave absorption materials (MAM). In an effort to promote sustainable and environmentally friendly solutions, researchers have turned their attention to waste materials as a potential resource for the development of efficient microwave (MW) absorbers. In order to lessen the effects of electromagnetic (EM) pollution, ferrites are frequently used as microwave-absorbing materials. However, the insufficient dielectric loss capacity is the fundamental constraint that limits their application. The MnFe2O4 was produced independently, while activated carbon (AC) was created using coconut shell. The MnFe2O4/AC composite was subsequently synthesized using a hydrothermal approach. From the research, the dielectric loss and magnetic loss of the S2 composite operate together. The incorporation of magnetic components contributes to the outstanding magnetic loss ability, while the nano-domain, hopping mechanism of the resonance effect is responsible for the improved dielectric qualities. S2 exhibits a minimum reflection loss of ‐38.4 dB at a thin thickness of 1.8 mm with an effective absorption bandwidth (EAB) of 6.2 GHz at the same thickness from 11.2 to 18 GHz. MnFe2O4/AC shows promise as a novel class of EM absorption materials because of their simple fabrication and high EM dissipation capacity. [Display omitted] •Activated carbon (AC) was prepared from coconut shell waste.•AC-encased MnFe2O4 composites with porous microstructures were synthesized.•The encasing of MnFe2O4 in porous structure elevated intrinsic permittivity and dielectric losses.•The porosity in microstructure amplified interfacial polarization leading to attenuation mechanism and conductance losses.•Effective absorption bandwidth is 6.2 GHz at 1.8 mm and Rlmin is −38.41 dB.