Challenges and Strategies for Addressing the Sensitivity-Detection Range Trade-Off in Flexible Pressure Sensors.

Flexible pressure sensors, as core devices in the field of flexible electronics, exhibit great potential for applications in wearable health monitoring, intelligent robotics, and human-machine interaction. This huge application potential is attributed to their excellent mechanical flexibility, conformability, and real-time response capabilities. However, during performance optimization, these sensors encounter a critical bottleneck, namely the inherent trade-off between high sensitivity and a wide detection range: High sensitivity typically relies on microstructures or interfaces with low stiffness that are prone to deformation, yet these are susceptible to structural saturation or damage under elevated pressures (>10 kPa). Conversely, a wide detection range requires the sensor to possess high structural robustness and resistance to deformation, which often results in weak signal responses in the low-pressure regime. To overcome this challenge, this review systematically elaborates on the root causes of this inherent trade-off, which makes it challenging to achieve high sensitivity and a wide detection range simultaneously. It primarily highlights various innovative strategies proposed in recent years to address this issue through microstructural design, including conventional microstructures, nanofiber microstructures, biomimetic microstructures, and synergistic microstructures. Finally, future research directions are outlined to provide theoretical guidance and technical references for developing next-generation high-performance flexible pressure sensors.