Fe3C nanocrystals encapsulated in N-doped carbon nanofibers as high-efficient microwave absorbers with superior oxidation/corrosion resistance. (30th June 2021)

• Record Type: Journal Article
• Authors: Sun, Yong; Wang, Yajing; Ma, Huijun; Zhou, You; Xing, Hongna; Feng, Wei; Feng, Juan; Shi, Zhenhua; Zong, Yan; Li, Xinghua; Zheng, Xinliang
• Is Part Of: Carbon. Volume 178(2021)
• Page Start: 515
• Page End: 527
• Publication Date: 2021-06-30
• Subjects: Fe3C/N-doped carbon nanofibers -- Microwave absorption -- Inoxidizability -- Corrosion resistance -- Lightweight; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2021.03.032
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: In addition to the demand of thin, lightweight, broadband and high-efficient characteristics, exploring microwave absorbents with superior resistance to oxidation and corrosion is urgently need for practical applications. Herein, carbon nanofibers embedded by α-Fe2 O3, Fe or Fe3 C nanocrystals are prepared through electrospinning technique followed by carbonization in different atmospheres. The one-dimensional structures can intertwine into three-dimensional conductive network, which is favored for energy dissipation. The Fe3 C/N-doped carbon nanofibers show boosting microwave absorption properties compared to the bare carbon, α-Fe2 O3 /C and Fe/C nanofibers. The Fe3 C/N-doped carbon nanofibers show an optimal reflection loss of −57.9 dB at 5.8 GHz with a thickness of 4.1 mm. Meanwhile, a reflection loss of −54.5 dB can be achieved at 17.8 GHz, when the absorber thickness is only 1.5 mm. The superior microwave absorption properties are attributed to the dipole polarization, interfacial polarization and ferromagnetic resonance, induced by the synergistic effect of Fe3 C nanocrystals and carbon nanofibers. Moreover, acid-soaking and air-annealing treatments reveal that the Fe3 C/N-doped carbon nanofibers show remarkable corrosion and oxidation resistance. This work suggests that encapsulating magnetic nanocrystals in dielectric carbon-based materials is an efficient strategy to construct high-efficient lightweight microwave absorbents with oxidation/corrosion resistance. Graphical abstract: Image 1 Highlights: Fe3 C embedded in C nanofibers are fabricated by electrospinning-carbonization route. Fe3 C/N–C nanofibers show optimal RL values of −54.5 dB with a thickness of 1.5 mm. The Fe3 C/N–C nanofibers show superior resistance to corrosion and oxidation.