Bridging dielectric-magnetic synergistic units with MOFs on fibers structure for high-efficient microwave absorption at low filler loading

• Published in: Carbon (New York) 2024-10, Vol.229, p.119444, Article 119444
• Main Authors: Ma, Xiaona, Pan, Fei, Xiu, Zheng, Li, Lixin, Zhang, Runa, Gu, Huiling, Sun, Chunhua, Gao, Yukui, Lu, Wei
• Format: Article
• Language: English
• Subjects: Electrospinning; Lightweight; Low filler loading; Magnetic-dielectric synergy; Metal-organic frameworks; Microwave absorption
• ISSN: 0008-6223
• DOI: 10.1016/j.carbon.2024.119444

Metal-organic framework (MOF) capable of magnetic-dielectric synergy loss mechanisms shine in the field of electromagnetic wave (EMW) absorption, whereas their high filler loading in the matrix remains a challenge and limit their practical application. Here, we mono-disperse bimetallic CoZn-MOF on conductive carbon nanofibers precursor via electrospinning technique and a following heat-treatment was employed to construct a Co–ZnO@NC carbon nanofiber (CNF) composites. The Co–ZnO particles with a size of 2 μm are evenly distributed within the carbon fibers, forming a unique structure resembling a “pearl necklace”. The introduction of one-dimension (1D) CNF can prolong the electron transport path and effectively reduces the percolation threshold of the composites. The composites are endowed with abundant heterogeneous interfaces, excellent magnetic-dielectric synergy and improved impedance matching, benefiting from which the obtained Co–ZnO@NC CNF composites demonstrate a maximum reflection loss (RLmin) of −54.5 dB at a thickness of 2.3 mm and an effective absorption bandwidth (EAB) of 8.12 GHz at a filler loading of merely 10 %. This study provides a feasible strategy for the design of MOF-derived absorbers with enhanced microwave absorption capacity at low filler loading. [Display omitted]