High Sensitivity Flexible Piezoresistive Sensor Based on the Synergistic Effect of Electrical Conductivity and Microstructure

ABSTRACT

We developed a crumpled microstructured piezoresistive sensor based on thermoplastic polyurethane (TPU) and alkalised MXene for high‐sensitivity flexible pressure detection over a wide range of 53 Pa–300 kPa. The TPU film with surface microstructures was fabricated via non‐woven fabric imprinting, and NaOH treatment converted planar MXene into 3D crumpled nanosheets with fewer surface ─F groups to strengthen TPU–MXene interfacial bonding. Benefiting from the synergistic effect of surface microstructures and crumpled conductive MXene, the sensor delivers segmented sensitivities of 4.14 kPa ⁻¹ (53 Pa–21 kPa) and 2.2 kPa ⁻¹ (21–63 kPa). It features a rapid 75 ms response time, 80 ms recovery time, tiny loading‐unloading hysteresis and stable sensing performance after 6000 compression cycles. Structural and chemical characterisations verify the optimised composite structure and pressure‐responsive conductive pathway evolution.