Highly sensitive triboelectric pressure sensors based on P(VDF-TrFE) electrospun nanofiber mat for wearable pulse monitoring

Abstract Wearable sensors based on the triboelectric effect have been developed as powerful tools for healthcare monitoring recently, enabling the acquisition of physiological signals. However, in the case of the pulse, the mechanical characteristics make it imperative due to the tiny pressure and low-frequency that the sensor measuring it be highly sensitive. This work focuses on designing a highly sensitive, diameter-tuned triboelectric pressure sensor (DPS) by controlling the applied voltage during P(VDF-TrFE) electrospinning, to achieve a higher triboelectric effect and thus greater sensitivity of the DPS. Specifically, by varying the applied voltage, we quantitatively compared changes in fiber diameter, β -phase fraction, and crystallinity. We present that higher electrospinning voltage yields thinner fibers with increased β -phase content and crystallinity, which enhance dielectric polarization and strengthen charge retention, thereby boosting the triboelectric effect. Consequently, the resulting high-sensitivity DPS precisely detects human pulse signals. The fabricated DPS achieved remarkable sensitivity (0.03044 nA · Pa −1 ) and a high coefficient of determination (∼99.7%), maintaining stable performance over 20 000 cycles. Reliable pulse waveforms can be detected at the carotid, radial, and brachial arteries, and validation against a commercial pulse sensor confirmed its accuracy of 97%. The DPS exhibits excellent sensitivity, durability, and validated applicability in human pulse monitoring, underscoring its potential for integration into next-generation wearable healthcare and self-powered physiological monitoring systems.