Phthalocyanine-mediated interfacial self-assembly of magnetic graphene nanocomposites toward low-frequency electromagnetic wave absorption

Abstract

Exploring multi-component composite is promising for advanced electromagnetic wave (EMW) absorption materials, yet challenged by balancing low-frequency absorption and cost-effective preparation mode. Herein, a series of dielectric-magnetic nanocomposites are fabricated as EMW absorbers via facile phthalocyanine-mediated interfacial self-assembly approach. Phthalocyanine could act as a functional reagent to modify magnetic Fe3O4 nanosphere and guarantee the self-assembly with reduced graphene oxide nanosheet simultaneously. Owing to the flexible self-assembly, the as-synthesized ternary nanocomposite exhibits highly tunable EMW absorption performance toward low-frequency absorption. The minimum reflection loss reaches −49.0 dB (99.998 % wave absorption) simultaneously at a low frequency of 5.4 GHz and a high frequency of 8.3 GHz, which displays superb absorption efficiency in both the C band and X band. The phthalocyanine-mediated dielectric-magnetic synergy endows the nanocomposite with enhanced impedance matching and multiple dissipation pathways. This study demonstrates a convenient strategy for the rational design of low-frequency EMW absorbers with high-efficiency absorption.