Highly sensitive and flexible humidity sensor based on carbon nanotubes and maltodextrin

Carbon nanotube (CNT) humidity sensors are potential for the application in e-skins. However, the sensitivity and response/recovery speed are not satisfied. Herein, we design a composite of CNTs and hydrophilic maltodextrin. The CNT/maltodextrin humidity sensor demonstrates a sensitivity of 69% and a short response and recovery time of 56 s/3 s. The CNT/maltodextrin humidity sensor showed strong robustness during peeling test and cyclic bending process. Finally, the flexible humidity sensor was demonstrated to detect finger movement.