Mesoporous MXene nanosheets/CNF composite aerogels for electromagnetic wave absorption and multifunctional response

To acquire excellent wave-absorbing materials with broadened applications, transition metal carbides (Ti 3 C 2 T x , MXene) have been the research focus. However, the high conductivity of MXene limits its electromagnetic wave (EMW) absorption capability; meanwhile, the inferior mechanical properties of MXene-based aerogels severely restrict their applications. Here, porous MXene (PMXene) nanosheets were prepared by hydrogen peroxide etching, which was then physically and chemically crosslinked with cellulose nanofibres (CNF) to successfully prepare PMXene/CNF composite wave-absorbing aerogels with excellent mechanical properties. PMXene/CNF aerogel achieved a minimum reflection loss (RL min ) of − 72.27 dB and an effective absorption bandwidth (EAB) of 5 GHz at a thickness of 1.63 mm without any magnetic component. The aerogels exhibited excellent environmental stability at a density of 12.5 mg/cm 3 , including fatigue resistance (100 compression cycles, 0.075 energy loss efficiency) and low-temperature resistance. Refining the mechanical properties exploits the aerogel’s potential for motion monitoring and electronic skin applications. In addition, the aerogels integrate properties such as water–oil separation, photothermal conversion, and thermal insulation (thermal conductivity of 0.045 W/(m-K)). Therefore, multifunctional PMXene/CNF aerogels have a broad potential for future application in the defence industry, electronic devices, and smart wearable fields.