Confined Diffusion Engineering of FeCoNi‐Embedded Hollow Carbon Microcage toward Controllable Electromagnetic Wave Absorption and Anticorrosive Polyvinylidene Fluoride Composite in Marine Environment
Qingfu Ban, Yuejie Song, Luwei Li, Huilin Zhang, Xinyao Wu, Jie Liu, Yusheng Qin, Di Lan, Tiantian Zhang, Jie Kong
Abstract
Abstract Rational regulation of hollow magnetic‐dielectric composites is becoming a leading strategy for achieving superior electromagnetic (EM) wave absorption. However, the simple fabrication of such composites remains a challenge. Herein, a confined diffusion engineering strategy is exploited to prepare hollow magnetic‐dielectric microcages, specifically FeCoNi@NCMs‐C x T y . Driven by Kirkendall effect, the alloying and migration of magnetic nanoparticles result in the formation of core–shell magnetic nanoparticle@graphitic carbon heterojunctions and graphitic carbon domains. Moreover, the metal content can be controlled by adjusting the etching of Ni 2+ and Fe 3+ on zeolitic imidazolate framework‐67, leading to a tunable magnetic response. The hollow FeCoNi@NCMs‐C x T y exhibits controllable EM wave absorption performance in the C∼Ku band, with the minimum reflection loss (RL min ) decreasing from ‐46.2 dB to ‐46.6 dB and ‐52.8 dB. Accordingly, the effective absorption bandwidth (EAB) expands from 1.63 GHz in the C band to 3.48 GHz in the C ∼ X band and 4.88 GHz in the X ∼ Ku band. To expand the application of FeCoNi@NCMs‐C x T y in marine environments, FeCoNi@NCMs‐C x T y /polyvinylidene fluoride composite is fabricated using a monolayer membrane‐mediated microscale processing method, showing anti‐corrosive properties. This study presents a novel strategy for fabricating high‐performance EM wave absorption composite that hold great potential in C∼Ku bands and for use in marine environments.