Flexible Hierarchical Porous Carbon Nanofibers/Aramid Nanofiber/ Ti 3 C 2 T x MXene Film for Electromagnetic Interference Shielding and Photothermal Conversion

ABSTRACT To address the challenge of simultaneously achieving high electromagnetic interference (EMI) shielding effectiveness and reduced electromagnetic wave reflection in MXene‐based materials, flexible composite films comprising hierarchically porous carbon nanofibers (HPCNFs), aramid nanofibers (ANF), and Ti 3 C 2 T x MXene were fabricated through vacuum‐assisted filtration and hot pressing. HPCNFs were introduced as a porous carbon component, while MXene served as a highly conductive shielding component. By regulating the assembly configuration, homogeneously mixed (H‐PAM) and laminated (L‐PAM) structures were constructed. The laminated architecture combined a porous HPCNFs/ANF layer with a conductive MXene layer. For electromagnetic wave incidence from the HPCNFs/ANF side, the optimized L‐PAM‐30 film exhibited an EMI shielding effectiveness of 31.8 dB, effectively blocking 99.93% of incident electromagnetic waves. Its reflection coefficient was 0.7154 for incidence from the HPCNFs/ANF side, compared with 0.955 for incidence from the ANF/MXene side. In addition, the composite films demonstrated mechanical flexibility, thermal stability, and photothermal conversion capability. This work provides an effective structural design strategy for reduced electromagnetic wave reflection in purely conductive MXene‐based shielding materials.