Dual-Dielectric-Layer-Based Iontronic Pressure Sensor Coupling Ultrahigh Sensitivity and Wide-Range Detection for Temperature/Pressure Dual-Mode Sensing.

Abstract

Iontronic pressure sensors are widely used in human motion monitoring and human-machine interactions owing to their high sensitivity, wide measurement range, and excellent resolution. However, conventional dielectric layer designs often involve complex fabrication processes, high costs, and limited performances. This paper proposes a novel sensor structure, the dual-dielectric-layer iontronic pressure sensor (DLIPS), which integrates high- and low-permittivity layers. Validated using silkworm cocoon ion gel and open-cell polyurethane foam as dielectrics, the DLIPS exhibited ultrahigh sensitivity (72548.7 kPa-1), a wide working pressure range (0.001-420 kPa), an exceptionally low detection limit (0.832 Pa), and remarkable durability exceeding 5000 cycles. By leveraging the distinct responses of the capacitance and resistance to pressure and temperature, the sensor can simultaneously measure both parameters. A deep learning regression model is integrated to decouple the mixed temperature and pressure signals, enabling accurate identification. Owing to its ultrahigh sensitivity and capability to detect minute pressure fluctuations, the DLIPS exhibited strong potential for skin-mounted silent speech recognition systems, achieving a recognition accuracy of up to 98.5%. Furthermore, the DLIPS provides a cost-effective and scalable approach for fabricating ultrahigh-sensitivity pressure sensors, underscoring its versatility in wearable technology applications.