Hua Tianxiang, Guo Hao, Qin Jing, Wu Qixin, Li Lingying, Qian Bo
School of Nano-Tech and Nano-Bionics, University of Science and Technology of China China
Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences China.
RSC Adv. 2022 Sep 1;12(38):24980-24987. doi: 10.1039/d2ra02951k. eCollection 2022 Aug 30.
Two-dimensional (2D) transition-metal carbides and nitrides (MXenes), especially TiCT nanosheets, offer high conductivities comparable to metal, and are very promising for fabricating high performance electromagnetic interference (EMI) shielding materials. Due to the weak gelation capability of MXenes, MXene/graphene hybrid aerogels were mostly studied. Among those studied, anisotropic hybrid aerogels showed excellent electrical properties in certain direction due to the intrinsic anisotropic properties of 2D materials. However, the present preparation methods for anisotropic hybrid aerogels lack freedom of geometry, and their electrical performances still have room for improvement. In this study, based on our previous work, the lamellar TiCT MXene/graphene hybrid aerogels generated by 3D printing with TiCT MXene/graphene oxide (GO) water-TBA dispersions demonstrated enhanced conductivity and electromagnetic interference (EMI) shielding performance. The addition of MXene deeply influenced the lamellar structure of the hybrid aerogels, and made the structure more ordered than that in the 3D printed lamellar graphene aerogels. The printed lamellar MXene/graphene hybrid aerogels achieved a maximum electrical conductivity of 1236 S m. The highest EMI shielding efficiency (EMI SE) of the hybrid aerogels was up to 86.9 dB, while the absolute shielding effectiveness (SSE/) was up to 25 078.1 dB cm g at 12.4 GHz. These values are higher than those of most reported anisotropic MXene-based nanocomposite aerogels.
二维（2D）过渡金属碳化物和氮化物（MXenes），尤其是TiCT纳米片，具有与金属相当的高电导率，在制造高性能电磁干扰（EMI）屏蔽材料方面非常有前景。由于MXenes的凝胶化能力较弱，大多研究的是MXene/石墨烯混合气凝胶。在这些研究中，由于二维材料固有的各向异性特性，各向异性混合气凝胶在特定方向上表现出优异的电学性能。然而，目前各向异性混合气凝胶的制备方法缺乏几何形状的自由度，其电学性能仍有提升空间。在本研究中，基于我们之前的工作，用TiCT MXene/氧化石墨烯（GO）水-TBA分散体通过3D打印生成的层状TiCT MXene/石墨烯混合气凝胶表现出增强的导电性和电磁干扰（EMI）屏蔽性能。MXene的加入深刻影响了混合气凝胶的层状结构，使其结构比3D打印的层状石墨烯气凝胶更有序。打印的层状MXene/石墨烯混合气凝胶的最大电导率达到1236 S m。混合气凝胶的最高电磁干扰屏蔽效率（EMI SE）高达86.9 dB，而在12.4 GHz时的绝对屏蔽效能（SSE/）高达25 078.1 dB cm g。这些值高于大多数报道的基于MXene的各向异性纳米复合气凝胶的值。
