Heterotypic CoNi Nanostructure Anchored on Porous Carbon Fibers for High-Performance Electromagnetic Wave Absorption

To achieve high-performance microwave absorbers with broadband absorption, strong attenuation, thin thickness, and lightweight properties, current research focuses on optimizing impedance matching through microstructure design engineering and multicomponent integration. In this paper, porous carbon fibers loaded with heterotypic CoNi nanostructures are prepared via an integrated electro-blowing spinning, hydrothermal treatment, and calcination approach. The engineered heterotypic CoNi nanostructures act as compensators to optimize impedance matching while generating substantial interfacial polarization and promoting multiple electromagnetic wave reflection/scattering. The three-dimensional (3D) porous carbon fiber frameworks serve as a structural foundation, establishing conductive networks to enhance conduction loss, while providing growth sites for heterotypic CoNi nanostructures. Benefiting from microstructure design engineering and multicomponent integration, the composites achieve synergistic magnetic/dielectric losses, improved impedance matching, and enhanced electromagnetic wave attenuation. As a result, the optimized cactus-like CoNi/PCF-UN architecture assembling with surface nanoneedles and nanosheets exhibits exceptional absorption performance: a minimum reflection loss (RL_min) of -40.32 dB at 14.29 GHz and an effective absorption bandwidth (EAB) of 6.25 GHz at 2 mm thickness. This work provides valuable insights for developing high-performance microwave absorbers through multicomponent integration and microstructure design engineering.