Graphene composite aerogel for highly efficient and multifunctional EMI shielding via dielectric-magnetic synergy strategy

The accelerated growth of modern electronics and devices has drawn considerable attention for the exploration and fabrication of innovative electromagnetic interference (EMI) shielding materials. Due to its layered porous architecture and distinctive characteristics, graphene aerogel is considered an appropriate candidate for advanced EMI shielding materials. Nonetheless, developing effective EMI shielding materials from graphene aerogel is challenging due to its moderate electrical conductivity. In this study, motivated by the concept of dielectric-magnetic synergy strategy, we present a graphene composite aerogel incorporating CoFe₂O₄ nanoparticles (NPs) and Ag nanowires (NWs) as enhancements. The CoFe₂O₄ NPs/Ag NWs/graphene composite aerogel, benefiting from the synergistic effects of CoFe₂O₄ NPs, Ag NWs, and graphene aerogel, demonstrated exceptional EMI shielding capabilities. Specifically, the CoFe₂O₄ NPs/Ag NWs/graphene composite aerogel (5 mm) offered an optimal shielding effectiveness of 67.4 dB, which was 247% of the graphite aerogel. Meanwhile, it exhibited a remarkable low density of 0.048 g/cm³ and a high specific shielding effectiveness value of up to 1291.67 dBcm³/g. In addition, it also showed superior Joule heating performance and hydrophobicity.