Highly Stable Polystyrene Microsphere‐Modified 2D MXene‐Based Flexible Pressure Sensor for Underwater Impact Detection

ABSTRACT Underwater impacts are a leading cause of numerous accidents, and pressure sensors are essential for detecting them. However, the inherent characteristics of existing rigid pressure sensors make it difficult to effectively detect impacts. Here, we fabricate 3D layered polystyrene/MXene nanocomposite films by incorporating polystyrene microspheres into MXene nanoflakes, which exhibit outstanding flexible pressure‐sensing performance. Finite element analysis indicates that the presence of polystyrene microspheres modulates the pressure‐sensing pathway of nanocomposite films by adjusting stress distribution. The sensitivity of the sensor based on this nanocomposite film has been improved by 4005.67% compared to pristine MXene films. Meanwhile, it maintains stable performance even under bending conditions, with sensitivity decreasing by only 6.1%. Ultimately, the sensing array system based on this sensor achieves effective detection of simulated underwater impacts. This work will introduce a novel approach to developing flexible sensing materials and arrays for effectively detecting underwater impacts.