Structural design and electromechanical response characteristics of hierarchical LM/MXene/TPU piezoresistive pressure sensor for wide-range human motion detection

The rapid advancement of wearable electronics has spurred growing interest in flexible piezoresistive pressure sensors owing to their wide detection range and cost-effectiveness. Nevertheless, achieving high sensitivity across a broad pressure spectrum while maintaining robust cycling stability remains a significant challenge. Herein, we present a hierarchical LM/MXene/TPU flexible piezoresistive sensor featuring a novel interlocked hierarchical architecture, in which laser-patterned slit arrays conformally wrap around opposing microsphere arrays under applied pressure. This multiscale interfacial design dynamically regulates conductive contact evolution, thereby enabling both high sensitivity and a broad pressure response range. The sensor exhibits an ultrahigh sensitivity of 640.01 kPa -1 in the low-pressure region (≤1.2 kPa), a wide linear detection range of 0.25-100 kPa, rapid response/recovery times of 170/183 ms, and stable performance over 1,000 loading-unloading cycles. In addition, the device demonstrates excellent applicability in real-time human motion monitoring, speech recognition, and physiological signal detection. These results highlight the strong potential of the proposed sensor for next-generation wearable health-monitoring systems and human-machine interaction technologies.