Cellulose Nanocrystals/Carboxylated Multiwall Carbon Nanotubes/Ti₃C₂T_x Hybrid Aerogels for Electromagnetic Interference Shielding

Ultralight and mechanically robust materials with high-efficiency electromagnetic interference (EMI) shielding performance are imperative to meet the evolution of portable electronic equipment. However, it remains challenging to balance ultralight and robust mechanical performances with excellent EMI shielding properties. Herein, anisotropic cellulose nanocrystals/carboxylated multiwall carbon nanotubes/Ti 3 C 2 T x MXene (CCM) hybrid aerogels are fabricated by methyltrimethoxysilane treatment and unidirectional freeze-drying. Successful assembly of multidimensional nanomaterials through Si–O–Si nanoribbons helps to realize lightweight, hydrophobicity, thermal insulation, and mechanical properties, as well as high electrical conductivity. The obtained hybrid aerogel displays a residual height of 76.38% at 50% strain after 50 compression cycles and a water contact angle of 120.7° in the axial direction. The average specific EMI shielding effectiveness of the anisotropic cellulose nanocrystals/carboxylated multiwall carbon nanotubes/Ti 3 C 2 T x MXene hybrid aerogel could reach up to 14,030.22 dB·cm 2 ·g –1, surpassing major reported materials. Multifunctional and anisotropic hybrid aerogels are promising in the field of electromagnetic protection engineering.