Graphene reinforced nanoarchitectonics of 3D interconnected magnetic-dielectric frameworks for high-efficient and anti-corrosive microwave absorbers

Abstract

The combination of high efficiency and environmental stability is vital to promote the commercial applications of microwave absorption (MA) materials, yet remains challenging in the absence of facile routes. Here, we put forward a graphene-reinforced construct approach for one-pot synthesis of 3D interconnected magnetic-dielectric frameworks via pre-functionalization and subsequent assembly. Multiple interactions among discrete precursors are capable of manipulating the confined growth and interfacial self-assembly. Significant enhancements in MA properties are triggered in a straightforward manner using ultralow feeding fractions of graphene oxide nanosheet. The minimum reflection loss is up to -60.1 dB (99.9999% wave absorption) and the effective absorption bandwidth reaches 5.9 GHz (almost covering the Ku band). Remarkably, based on the optimization by ultralow concentrations of graphene, the as-prepared nanoarchitecture simultaneously integrates strong absorption, broad bandwidth, and low matching thickness. The embedded graphene nanosheets serve as high-speed electron transmission channels and hollow resonance cavities, facilitating multimode attenuations and impedance-matching characteristics. Meanwhile, the graphene-reinforced framework suppresses the corrosion of magnetic components, whose corrosion rate reduces by an order of magnitude. This study provides a simple procedure to boost magnetic-dielectric absorbers for comprehensive MA performances and enhanced corrosion resistance.