Ultrathin MXene/Calcium Alginate Aerogel Film for High-Performance Electromagnetic Interference Shielding

Ultrathin and high-performance electromagnetic interference (EMI) shielding materials are urgently demanded for modern microelectronic devices. 2D metal carbides (MXenes) are considered as a promising EMI shielding material due to its metallic conductivity. In this study, sodium alginate is applied as interlayer spacer for Ti 3 C 2 T x nanosheets, which not only prevents the restacking of lamella structure but also serves as building blocks for the sponge-like structure. Ultrathin Ti 3 C 2 T x /calcium alginate (CA) aerogel films with sponge-like structure and only tens of microns thickness are prepared through divalent metal ion induced crosslinking, vacuum-assisted-filtration induced self-assembly, and freeze-drying. Taking advantage of its sponge-like structure, which facilitates the dissipation of incident electromagnetic waves through multireflection and scattering Ti 3 C 2 T x /CA aerogel film, presents excellent EMI shielding effectiveness (54.3 dB) at a very low thickness of 26 µm. Furthermore, Ti 3 C 2 T x /CA aerogel film shows an outstanding specific EMI shielding efficiency (17586 dB cm 2 g −1 ), which is superior to most reported synthetic materials. The preparation of ultrathin Ti 3 C 2 T x /CA aerogel film provides facile strategy for designing and fabricating high-performance MXene-based EMI-shielding materials, which is highly desirable for various applications including aerospace and smart electronic devices.