Metal-organic framework confined preparation of hydrophobic nickel/carbon nanofibers for lightweight and enhanced microwave absorption

The use of a metal-organic framework (MOF) confinement strategy to achieve controllable growth and even allocation of magnetic metal nanoparticles (NPs) in carbon nanofibers (CNFs) can significantly improve the microwave absorption performance of absorbers. Herein, we constructed Ni-MOF in the spinning solution and prepared Ni/CNFs with confined structures using electrospinning combined with carbon thermal reduction. The microstructure of Ni/CNFs was regulated by adjusting the amount of organic ligands added. Ni NPs with single domain size and uniform allocation could optimize impedance matching and enhance electromagnetic synergistic effects, which was beneficial for enhancing microwave absorption performance. When the additional amount of organic ligands was 4 wt%, the absorber reached the optimal microwave absorption performance as the filling ratio was only 3 wt%, the minimum reflection loss (RL) reached −24.9 dB at 13.6 GHz when the thickness was 2.0 mm, and the effective bandwidth (EBW) attained 5.22 GHz. In addition, the excellent hydrophobic performance of nanofibers (NFs) endowed them with potential self-cleaning functions. In addition, to verify the practical application value of the prepared samples in radar stealth technology, we used computer simulation technology (CST) to simulate the samples. Therefore, this work provides a new approach for the controllable preparation of novel magnetic metal/carbon fiber-based absorbers, and also provides a model reference for the controllable growth of magnetic metal particles in the carbon thermal reduction reaction process.