Simultaneous in-situ reduction and foaming synthesis of magnetic MXene/rGO porous films for enhanced electromagnetic interference shielding

Lightweight, porous and conductive films represent a promising solution for effective electromagnetic interference (EMI) shielding. Nevertheless, the simultaneous integration of porous architectures and electromagnetic synergistic components remains a significant challenge. Herein, this work presents an innovative fabrication strategy that combines sequential vacuum-assisted filtration with in-situ hydrazine hydrate-mediated foaming. This approach simultaneously constructs a 3D porous architecture while reducing nickel precursors to magnetic nanoparticles, ultimately yielding lightweight MXene/rGO-Ni (fMG-Ni) porous films with tunable electromagnetic properties. The engineered porous architecture facilitates multiple internal reflections and scattering of electromagnetic waves, while the synergistic combination of conductive MXene/rGO and magnetic Ni components induces complementary dielectric and magnetic loss mechanisms. These combined effects endow the porous film with effective EMI shielding properties. The optimized fMG-Ni porous film with an ultralow density of 0.246 g/cm³ and a minimal thickness of 163 μm exhibits an outstanding electrical conductivity of 1,062.81 S/m and an EMI shielding effectiveness of 37.9 dB in X-band, achieving a high specific shielding efficiency of 9,452 dB·cm²·g⁻¹ and long-term stability (94.3% retention after 5 months). This work establishes a new paradigm for designing ultralight, high-performance EMI shielding materials for next-generation aerospace, flexible electronics and telecommunication applications.