Ultrasensitive, signal-complementary piezo-capacitive pressure sensor for complex physiological monitoring and HMI

Disentangling complex, concurrent dynamic and static mechanical stimuli remains a challenge for next-generation wearable devices. Here, we propose a vertically integrated flexible dual-modal pressure sensor that synergistically combines a lead-free flexibility piezoelectric sensor (FPS) and a bioinspired iontronic capacitive sensor (ICS) to address this limitation. The FPS employs a three-dimensional interwoven potassium sodium niobate piezoceramic textile embedded in polydimethylsiloxane, achieving efficient stress transfer for dynamic sensing with high piezoelectricity (piezoelectric constant d 33  = 38 pC N −1 , S Vmax  = 0.7 kPa −1 ). In parallel, the ICS incorporates a peak-valley microstructured ionogel dielectric layer, enabling ultrahigh static sensitivity ( S Cmax  = 2599.65 kPa −1 ) through pressure-modulated interfacial contact area. This dual-mode architecture generates complementary signals: transient piezoelectric voltage for high-frequency dynamics and capacitive displacement for static/quasi-static loads. This capability overcomes the single-mode limitation in disentangling concurrent static and dynamic sensing, achieving exceptional accuracy in discriminating loads, recognizing sound, analyzing high-pressure gait, and identifying handwriting. This study not only establishes an innovative strategy for dual-mode pressure sensor design but also bridges the critical gap between complex mechanical stimuli decoding, medical diagnostics, and adaptive human-machine interaction (HMI).