Enhanced Sensitivity and Durability of f-MXene/MXene/PU Sponge-Based Pressure Sensors for Real-Time Health Monitoring

Abstract: The development of flexible and wearable pressure sensors has gained significant attention due to their potential applications in health monitoring, robotics, and human-machine interfaces. However, existing pressure sensors face challenges such as limited sensitivity, narrow detection ranges, and difficulties in scalable fabrication. In this study, we propose a novel multi-layer f-MXene/MXene/PU sponge-based flexible pressure sensor, designed to address these limitations. The sensor was fabricated using a dip-coating method, where functionalized MXene (f-MXene) and MXene nanosheets were sequentially deposited onto a polyurethane (PU) sponge substrate. This structure enhances the sensor's mechanical flexibility, electrical conductivity, and air permeability while preserving its compressibility. Experimental results demonstrate that the optimized multilayer f-MXene/MXene/PU sensor exhibits a high-sensitivity of 7.4 kPa-1 over a broad pressure-sensing range of 58 kPa. Additionally, the sensor features rapid response and recovery times (340 ms and 300 ms, respectively) and maintains stable performance over 200 consecutive loading–unloading cycles, indicating strong durability. Application tests further validate its capability to detect a wide range of pressures, from subtle touch interactions (e.g., finger pressing) to high-force applications (e.g., foot stepping). These findings highlight the potential of MXene-based composite sensors in wearable electronics and real-time pressure monitoring. Future research should focus on enhancing the long-term stability of MXene against oxidation and integrating wireless communication modules for smart sensor applications.