Structural engineering of MOF–MXene-infused carbon foam for ultra-efficient electromagnetic interference shielding

Abstract

The development of advanced, lightweight electromagnetic interference (EMI) shielding materials with exceptional stability and performance is top priority for the effective mitigation of electromagnetic pollution. Herein, we report a hierarchical composite architecture based on zeolitic imidazolate framework-11 (ZIF-11) and titanium carbide MXene (Ti₃C₂T_x) nanosheets with precise control over variable composite loadings (14 wt%, 16 wt%, and 18 wt%) within the mesoporous carbon foam scaffold. The resulting composite exhibits a three-dimensional conductive framework with enhanced surface area and optimized electrical conductivity achieved through structural and interfacial engineering that synergistically enhances EMI shielding effectiveness. The structural characteristics, phase purity, surface morphology, vibrational modes and thermal stability of the as-synthesized composite were systematically investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Among the three compositions investigated, the optimal composite with 18 wt% filler-impregnated carbon foam achieved an outstanding EMI shielding effectiveness of 64 dB in the X-band frequency range (8.2–12.4 GHz), primarily attributed to combined dielectric loss, interfacial polarization, and improved electrical conductivity. Thermogravimetric analysis further reveals enhanced thermal stability of the as-synthesized composite up to ∼560 °C, highlighting the structural robustness of the system under operational conditions. These results demonstrate a scalable and rational design strategy for developing advanced EMI shielding materials, offering an augmented and robust solution for enhancing electromagnetic shielding properties for the next-generation miniaturized electronics and communication systems.