Ultralight Ti₃C₂Tx/CNF aerogel with outstanding electromagnetic interference shielding efficiency

MXene is widely used as electromagnetic interference (EMI) shielding material due to its excellent electrical conductivity. However, nanosheet structure leads to agglomeration, which has certain limitations on the application. Inspired by bacterial cellulose (BC) has good adhesion and can transform into carbon nanofibers (CNF) after heat treatment, we prepared Ti₃C₂Tx/CNF aerogels by bidirectional freeze-drying method and heat treatment. Under the bonding effect of BC, the highly conductive phase Ti₃C₂Tx nanosheets were connected into a periodic porous aerogels, which hindered the agglomeration of Ti₃C₂Tx nanosheets. BC is converted into CNF after heat treatment, forming a conductive network in aerogel. It significantly improves the EMI shielding performance to 44.5 dB at a thickness of 2 mm. The density of the obtained aerogel is only 24 mg•cm⁻³, and the specific EMI shielding efficiency (SSE, shielding value/density) value reaches 1844.6 dB cm³ g⁻¹, which has a good comprehensive performance.