Compressible, elastic and 3D porous Ti3C2Tx MXene/RGO/CNCs composite aerogel for electromagnetic wave absorbing

Incorporating compressibility, elasticity, and porous structures into microwave- absorbing materials will facilitate electromagnetic wave absorption (EMA) and improve environmental adaptability for practical applications. Herein, a strategy to prepare Ti3C2Tx MXene/reduced graphene oxide (RGO)/ cellulose nanocrystals (CNCs) aerogels via a directed freezing method to design three-dimensional structures and strengthen the interaction between Ti3C2Tx MXene and RGO lamellae is demonstrated. Oriented structures and the addition of CNCs benefit structural stability while achieving superior absorption performance by forming perfect impedance matching and multiple polarization effects. Interestingly, the prepared MXene/RGO/CNCs (MRC-20) aerogel delivers the prominent EMA performance in reported MXene-based absorbing materials, with a minimal reflection loss (RLmin) of - 72.32 dB at 12.0 GHz corresponding to a matching thickness of 2.56 mm and an effective absorption bandwidth (EAB) of 4.96 GHz at 1.88 mm with an RLmin of - 59.87 GHz. Furthermore, by tuning the content of CNCs, the MRC-20 aerogel exhibits the highest stress (37.2 kPa) at 70% compressive strain and demonstrates the stability of the compression cycle. These intriguing features make the hybrid aerogel stand out among numerous absorbers.