Green Manufacturing of Anisotropic MXene/Carboxymethyl Chitosan Aerogels from Renewable Biomass for Multifunctional Wearables

With the rapid growth of flexible electronics and outdoor sensing technologies, developing novel materials that combine high sensitivity, mechanical robustness, and multifunctionality has become a key focus. Traditional materials often suffer performance degradation under extreme conditions, limiting their thermal management, infrared stealth and sustainable development. In this study, MXene/carboxymethyl chitosan (MXene/CCS) composite aerogels with an ordered channel structure were fabricated via directional freeze-drying. These aerogels exhibited significant improvements in mechanical strength and electrical conductivity, with a compressive strength reached 195 kPa along the ice crystal growth direction and 79 kPa in the perpendicular direction under 10% strain and a sensitivity of up to 14.60. The response and recovery times were under 88 ms, demonstrating excellent dynamic response. As a piezoresistive sensor, the aerogel could detect subtle human movements and external stimuli, enabling applications such as Braille recognition and Morse code output. Additionally, the aerogels showed outstanding photothermal conversion, thermal management, oil–water separation, and antibacterial performance, with inhibition efficiencies over 50% against Escherichia coli and Staphylococcus aureus. This work presents a promising strategy for developing environmentally friendly and multifunctional MXene-based flexible electronics, with potential applications in intelligent sensing, thermal management, environmental camouflage, and oil–water separation.