Confined magnetic nickel nanoparticles in carbon microspheres with high-performance electromagnetic wave absorption in Ku-band

• Published in: Composites communications 2024-11, Vol.51, p.102099, Article 102099
• Main Authors: Wang, Chao, Huang, Mengqiu, Zhu, Hao, Wang, Lei, You, Wenbin, Che, Renchao
• Format: Article
• Language: English
• Subjects: Dielectric dissipation; Magnetic loss; Microwave absorption; Ni@C microspheres; Spray-drying
• ISSN: 2452-2139
• DOI: 10.1016/j.coco.2024.102099

Composition and structure regulation is the primary strategy in preparing high-performance electromagnetic (EM) wave absorption materials. Herein, magnetic-dielectric synergy Ni@C microspheres were fabricated to obtain the high-performance electromagnetic (EM) wave absorption performance. Firstly, the Ni-containing precursor microspheres were obtained via the spray-drying technology. Secondly, reduced magnetic Ni nanoparticles (NPs) were confined in the N-doped carbon microspheres after pyrolysis treatment in the H2/Ar atmosphere. Duo to the existence of melamine, the distribution of Ni NPs and related EM parameters of Ni@C microspheres were efficiently regulated to seek the well impedance matching and EM responded ability. As results, as-synthesized Ni@C microspheres exhibited the minimum reflection loss (RLmin) of −48.2 dB and effective absorption bandwidth (EAB) of 5.7 GHz, covering almost Ku-band. This research represents a significant advancement in the development of magnetic-dielectric composite microspheres with superior absorption capacity, and it also provides a large-scale preparation strategy for electromagnetic wave absorbing materials. [Display omitted] •Magnetic-carbon Ni@C microspheres were fabricated via the spray-drying and pyrolysis treatment.•Obtained Ni@C-1 microsphere hold the RLmin of −48.2 dB and the EAB of 5.7 GHz at 2.0 mm thickness.•Synergistic dielectric dissipation and magnetic loss contributed to the electromagnetic wave absorption.