Humidity sensitive cellulose composite aerogels with enhanced mechanical performance

It is a long-standing issue to develop conductive polymer composites as humidity sensor with rapid response, high reproducibility and good long-term stability. Herein, a simple, efficient, and environmentally benign strategy was proposed to fabricate highly porous, robust and conductive cellulose composite aerogels. Owing to the intrinsic high specific surface area and well-defined electrically conductive network, the as-prepared cellulose composite aerogels were highly sensitive to water vapor with a relative resistance response value of as high as ~ 1000% at a CNT loading of 0.19 vol%. The dense hydrogen bonding network endowed high reproducibility and good long-term stability to cellulose composite aerogels. Moreover, a significant improvement in the mechanical properties of cellulose composite aerogels was achieved, outperforming neat cellulose aerogel with the increments of ~ 149.2% and ~ 242.1% in compressive strength and modulus, respectively. The green, robust, highly sensitive cellulose composite aerogels are in great potential need as humidity sensors in biology and automated industrial processes.