An Ultra‐Sensitive and Wide Strain Range Sensor via Commercial Rubber‐Based 3D Hyper‐Interface and Parallel Conductive Networks

Abstract The rapid growth in emerging fields has created historic opportunities for sensors, and crack‐based sensors have demonstrated enhanced sensitivity. However, the high sensitivity, wide strain range, and high linearity of flexible sensors have long been considered as an impossible trinity, proving difficult to achieve simultaneously in previous research. Herein, a multifunctional sensor consisting of conductive transition and sensitive layers on a supporting layer is fabricated by modulating 3D hyper‐interface (HPI) and a parallel circuit. The formation of 3D HPI layer between the transition layer and the supporting layer provides strong adhesion, endowing the transition layer with stretchability. Consequently, the sensor exhibits an unprecedented gauge factor (GF, 5.8 × 10 7 at 10% strain), a wide strain response range (50% strain), excellent mechanical stability (over 2700 cycles), a rapid response time (≈70 ms), and a simple preparation strategy. These features enable the sensor to monitor physiological activities with weak strains as well as human motion with large strains, and show potential applications in industrial safety, alongside applications for non‐contact sensing devices. This design strategy, based on commercial rubber, is easily scalable and can be translated to other systems, representing an important advance in fabricating sensors with ultra‐sensitivity and a wide strain response range.