Highly flexible and sensitive Ti₃C₂ MXene@polyurethane composites for piezoresistive pressure sensor

Flexible and wearable pressure sensors with subtle structure design provide timely and portable solutions for human motion detection. In this study, a simple and cost-efficient fabrication strategy for microcrack-designed pressure sensors based on Ti₃C₂ (MXene) and polyurethane (PU) is proposed. The MXene@PU composite-based pressure sensor presents superior conductivity, high stretchability and excellent strain resilience (under 80% compressive deformation), which benefits from the electrical conduction of MXene nanosheets and high pressure retraction elasticity of PU. Most importantly, the novel conductive network with enriched microcracks constructed by MXene endows the pressure sensor with not only high sensitivity (46 ms response time at 0.1% strain detection, GF≈0.8), but also excellent durability (500 cycles fatigue tests). Owing to the outstanding performance, human signals (wrist, elbow and knee) are accurately monitored by the obtained sensor. The findings demonstrate that this MXene-based pressure sensor exhibits potential as high-efficient sensing devices for health monitoring, wearable electronics and smart robots.