Construction of tunable and high-efficiency microwave absorber enabled by growing flower-like TiO2 on the surface of SiC/C nanofibers

• Published in: Journal of solid state chemistry 2021-12, Vol.304, p.122553, Article 122553
• Main Authors: Huo, Yashan, Zhao, Kang, Miao, Peng, Li, Fuping, Lu, Zhengxin, Meng, Qingnan, Tang, Yufei
• Format: Article
• Language: English
• Subjects: Electrospinning and hydrothermal approaches; Flower branch-like structure; Microwave absorption; TiO2@SiC/C nanofibers
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2021.122553

Flower branch-like TiO2@SiC/C composite nanofibers that are lightweight and have high-efficiency microwave absorption (MA) in the 2–18 ​GHz frequency range were fabricated via electrospinning and hydrothermal approaches. Phase analysis results showed the presence of rutile TiO2, β-SiC, and amorphous carbon in the composite nanofibers. Nanowhiskers grew randomly on the surface of the nanofibers along the (101) plane of rutile TiO2 nanocrystalline and formed a flower branch-like structure. The bionic morphology generated a great deal of heterojunctions and porous structures, which enable interfacial polarization, dipole polarization, conductance loss, multirelaxation, and suitable impedance matching through synergistic effects. Therefore, excellent wave-absorbing performance was achieved in the X and Ku bands when the composite nanofibers' filler loading was changed. The minimum reflection loss (RL) value was less than −45.3 ​dB with the thickness of less than 3 ​mm when the composite nanofibers absorber content was 10 ​wt%. Also, the maximum effective absorption bandwidth (EAB) exceeded 5 ​GHz. This study developed a neoteric structure to construct composite fibers loaded with nanowhiskers, and the TiO2@SiC/C nanofibers could be a remarkable candidate for broadband and efficient microwave absorbers. Also, the tunable wave-absorbing performance indicates a wide range of applications is possible under various environmental conditions. With conductive network, better dielectric loss and stronger interfacial polarization, the flower branch-like TiO2@SiC/C composite nanofibers exhibit optimized electromagnetic parameters and enhanced microwave absorbing capabilities. [Display omitted] •A neoteric approach to design SiC-based composite nanofibers loaded with TiO2 nanowhiskers.•The unique porous and bionic hierarchical structure is beneficial to improve the dielectric loss and impedance matching.•The flower branch-like TiO2@SiC/C composite nanofibers exhibit strong microwave absorption with a minimum of −45.3 ​dB.•Revealing the inner loss mechanism of enhanced microwave absorption properties.