High-Sensitivity Dual-Sensing-Layer Flexible Pressure Sensor Based on MWCNTs/SR Composites for Material Property Identification

In recent years, there has been a surge of research interest in flexible pressure sensors, driven by their outstanding application prospects in wearable devices, electronic skin, as well as other relevant application fields. Here, we propose a multilayer flexible resistive pressure sensor with high sensitivity using multiwalled carbon nanotube/silicone rubber (MWCNTs/SR) composites as the pressure-sensitive layer. Uniquely, a dual sensing layer was fabricated by combining a 3D-printed oblique-pyramid structure with an abrasive-paper template. In addition, an SR substrate bonded with copper foil was designed as an intermediate interconnect layer. Integrating these components into a three-layer architecture has significantly enhanced the overall performance. The sensor exhibits high sensitivity (17.33%/kPa), a low hysteresis error (2.74%), a wide sensing range (0–125 kPa), and long-term stability (7500 cycles). It can also detect the damage of its internal modules, and can identify the hardness of materials and evaluate the surface roughness of objects, indicating broad application prospects. This work guides rational fabrication and scalable application of high-performance flexible pressure sensors.