Variable Stiffness Flexible Wearable Pressure Sensors with Dual-Mode Switching Sensitivity and Working Pressure Range

The dilemma between sensitivity and the working pressure range in flexible pressure sensors restricts their general applicability. Herein the phase-change materials were introduced into carbon nanotube/polyurethane (CNT/PU) composites to create switchable dual-mechanical-mode membranes (SDMs). The developed SDMs pressure sensor can be switched between rigid and soft working modes. The soft mode exhibits an approximately 13.3 times improvement in sensitivity compared with the rigid mode, while the rigid mode offers a roughly 64% increase in the working pressure range compared to the soft mode. The SDMs pressure sensor shows excellent cyclic stability and an applicable response/recovery time. This soft/rigid dual-mode SDMs sensor has been successfully applied for sensing both small and large pressures, which paves an avenue for balancing sensitivity and the working pressure range in various scenarios.