Electro-magnetic dual-gradient MXene@Ni/Aramid nanofiber film for low-reflection electromagnetic interference shielding

Low-reflection electromagnetic interference (EMI) shielding materials have attracted increasing attention due to their capability to prevent secondary electromagnetic pollution, yet simultaneously achieving high EMI shielding effectiveness (SE) and low reflection remains a major challenge. In this study, heterostructure MXene@Ni hybrids were first synthesized, followed by the fabrication of a multilayered MXene@Ni/ANF film with an electro-magnetic dual-gradient structure via a layer-by-layer vacuum-assisted filtration process. The electro-magnetic dual-gradient structure was achieved by precisely controlling the MXene-to-Ni loading ratio and implementing a specific filtration sequence. The engineered gradient layered structure regulate the electromagnetic properties by modulating the mass ratio of MXene to Ni in each MXene@Ni/ANF layers. As a result, the composite film with precise control of the electro-magnetic gradient transition layers and reflection layer achieved excellent impedance matching and electromagnetic wave dissipation, ultimately resulting in remarkably efficient EMI shielding performance (37.6 dB) with low reflection characteristic (a low reflection coefficient of 0.72). This optimized structure ensures efficient electromagnetic wave absorption with minimal reflection, making it highly suitable for advanced EMI shielding applications.