Highly effective and tunable microwave absorber integrating multiscale attenuation behaviours derived from prussian blue analogue/graphene oxide aerogel

Abstract

Tunable and efficient absorption of graphene-based microwave absorbers are essential on the realms of electromagnetic compatibility and protection in various application scenarios. However, challenges arise owing to their limited microwave attenuation behaviors. Herein, CoNiFe Prussian blue analogue (PBA)-derived magnetic alloy@carbon nanocubes anchored on N-doped reduced graphene oxide (rGO) aerogels were achieved via CoNiFe-PBA nanocubes assisting assembly of GO and subsequent thermal annealing approach. Such three-dimensional (3D) graphene-based macroscopic architecture integrates multiple attenuation behaviours occurred across multiple length scales. Attributed to the synergy of multiple scattering, conduction loss, multiple heterogeneous interface and dipolar polarizations, and magnetic loss, the optimized CoNiFe-PBA/GO aerogel derivative simultaneously exhibits strong reflection loss and wide effective bandwidth with an ultralow filling content (1.1 wt%) at both X band (−66.01 dB and 5.2 GHz at 3.2 mm) and Ku band (−66.23 dB and 6.6 GHz at 2.6 mm). Multiscale assembly strategy of graphene-based electromagnetic functional materials from molecular level to macroscale proposed and demonstrated by this work shows promise for exploring tunable and efficient microwave absorbers.