As the rapid development of Bluetooth technology and 5G communication continues to accelerate, electromagnetic interference issues in the ISM band (2.4–2.48 GHz) for Bluetooth devices, as well as the n77 (3.3–4.2 GHz), n78 (3.3–3.8 GHz), and n79 (4.4–5.0 GHz) bands for 5G communications, have become increasingly severe. Now, researchers from Nanchang Hangkong University, Nanchang University, Jiangxi Agricultural University, and Fudan University, led by Professor Chongbo Liu, Professor Yuhui Peng, Professor Guangsheng Luo, and Professor Xuliang Nie, have presented a breakthrough method for controlling magnetic nanoparticle spacing and magnetic domain configurations. This work offers valuable insights into the development of next-generation low-frequency electromagnetic wave absorption materials that can overcome the Snoek limitation.
Why Magnetic Domain Configuration Control Matters
• Low-Frequency Electromagnetic Wave Absorption: Precise tuning of magnetic domain configurations enables effective attenuation of low-frequency EM energy in the S-band (2–4 GHz) and C-band (4–8 GHz), addressing critical electromagnetic interference and radiation pollution challenges.
• Breaking the Snoek Limit: The unique magnetic coupling phenomenon surpasses the Snoek limit in the low-frequency range, significantly enhancing permeability beyond what conventional ferromagnetic materials can achieve.
• Multifunctional Integration: The developed composites offer additional radar stealth and thermal insulation performances, making them suitable for extreme temperature conditions and complex application environments.
Innovative Design and Features
• Thermodynamically Controlled Coordination Strategy: A periodic coordination thermodynamical strategy is proposed to modulate magnetic domain configurations, achieved through aldimine condensation, coordination thermodynamics, and thermal reduction. This approach enables precise regulation of magnetic nanoparticle spacing from individual to coupled and ultimately to crosslinked domain configurations.
