In response to the global demand for sustainable development and high-performance flexible electronics, we report a sustainable strategy for fabricating multifunctional, conductive aerogels for these applications. The process involves the preparation of cellulose/MXene composite hydrogels through cellulose dissolution and regeneration, followed by in situ polymerization of polyaniline (PANI) and freeze-drying to obtain cellulose/MXene/PANI aerogels. Owing to the strong interactions among regenerated cellulose, MXene nanosheets, and PANI, the resulting aerogels exhibit a highly porous architecture, excellent electrical conductivity, and robust mechanical integrity. These features translate into outstanding electrochemical performance in solid-state supercapacitors, including high specific capacitance, excellent cycling stability, and good rate capability. The enhanced performance is attributed to the synergistic effects of the composite components and the structural stability of the cellulose matrix. Furthermore, the aerogels demonstrate remarkable flexibility and sensitivity, enabling accurate and stable detection of subtle human movements, making them suitable for applications in health monitoring and human–machine interfaces. The PANI surface activity and the large specific surface area of MXene also contribute to the aerogel’s effectiveness as a sensitive and efficient ammonia gas sensor. This work presents a sustainable and scalable approach for producing high-performance aerogels with broad applications in energy storage, environmental sensing, and wearable electronics.
