Silicone-Coated MXene/Cellulose Nanofiber Aerogel Films with Photothermal and Joule Heating Performances for Electromagnetic Interference Shielding

Aerogels with a larger specific surface area and lightweight property have aroused tremendous attention in recent years. Functional aerogel materials have shown applications in the fields of industry, environment, biomedicine, and so forth. Herein, multifunctional composite aerogels of cellulose nanofibers (CNFs), MXenes, and silicone have been achieved via a simple freeze-drying and post-coating process. CNFs with a one-dimensional nanostructure are employed for assisting the construction of three-dimensional frameworks to overcome the weak interlayer bonding force of MXene nanosheets. The resultant aerogel exhibits an electrical conductivity of ∼65.6 S m–1 and an EMI shielding of 39.5 dB. Meanwhile, the silicone coating makes MXene/CNF aerogel membranes hydrophobic, displaying an outstanding water-repellent feature, which is significant for maintaining a satisfactory lightweight of the aerogel in a wet environment. Especially, the silicone-coated MXene/CNF aerogel film also exhibits excellent Joule heating and photothermal performances. In particular, the aerogel shows a fast thermal response and a higher temperature range (30.2–141.4 °C in Joule heating and 30–91 °C in photothermal performance). Considering the characteristics of hydrophobicity, high EMI shielding efficiency, and superior Joule heating and photothermal performances, multifunctional silicone–MXene/CNF aerogel films will have promising applications in intelligent garments and EMI shielding fields.