High‑efficiency electromagnetic interference (EMI) shielding materials are of great importance for electronic equipment reliability, information security and human health. In this work, bidirectional aligned Ti₃C₂T_x@Fe₃O₄/CNF aerogels (BTFCA) were firstly assembled by bidirectional freezing and freeze-drying technique, and the BTFCA/epoxy nanocomposites with long-range aligned lamellar structures were then prepared by vacuum-assisted impregnation of epoxy resins. Benefitting from the successful construction of bidirectional aligned three-dimensional conductive networks and electromagnetic synergistic effect, when the mass fraction of Ti₃C₂T_x and Fe₃O₄ are 2.96 and 1.48 wt%, BTFCA/epoxy nanocomposites show outstanding EMI shielding effectiveness of 79 dB, about 10 times of that of blended Ti₃C₂T_x@Fe₃O₄/epoxy (8 dB) nanocomposites with the same loadings of Ti₃C₂T_x and Fe₃O₄. Meantime, the corresponding BTFCA/epoxy nanocomposites also present excellent thermal stability (T_{heat-resistance index} of 198.7 °C) and mechanical properties (storage modulus of 9902.1 MPa, Young's modulus of 4.51 GPa and hardness of 0.34 GPa). Our fabricated BTFCA/epoxy nanocomposites would greatly expand the applications of MXene and epoxy resins in the fields of information security, aerospace and weapon manufacturing, etc.

高效电磁干扰（EMI）屏蔽材料对电子设备的可靠性、信息安全和人体健康具有重要意义。在这项工作中，双向排列的Ti ₃ C ₂ T _x @Fe ₃ O ₄ /CNF气凝胶（BTFCA）首先通过双向冷冻和冷冻干燥技术组装，然后制备具有长程排列层状结构的BTFCA/环氧纳米复合材料。通过真空辅助浸渍环氧树脂制备。受益于双向排列的三维导电网络的成功构建和电磁协同效应，当Ti ₃ C ₂ T _{x的质量分数}和 Fe ₃ O ₄分别为 2.96 和 1.48 wt%，BTFCA/环氧树脂纳米复合材料显示出 79 dB 的出色 EMI 屏蔽效能，约为混合 Ti ₃ C ₂ T _x @Fe ₃ O ₄ /环氧树脂 (8 dB) 纳米复合材料的 10 倍具有相同负载量的 Ti ₃ C ₂ T _x和 Fe ₃ O ₄。同时，相应的BTFCA/环氧纳米复合材料也表现出优异的热稳定性（T_耐热指数198.7 °C）和机械性能（储能模量为 9902.1 MPa，杨氏模量为 4.51 GPa，硬度为 0.34 GPa）。我们制造的 BTFCA/环氧纳米复合材料将极大地扩展 MXene 和环氧树脂在信息安全、航空航天和武器制造等领域的应用。