Sensing–transducing coupled piezoelectric textiles for self-powered humidity detection and wearable biomonitoring

TLDR

Chemical sensor performance depends on target molecule perception and signal conduction, yet sensing and transduction are usually spatially and temporally independent, hindering miniaturization and integration. We propose a sensing‑transducing coupled strategy that embeds high‑piezoresponse Sm‑PMN‑PT ceramic into a moisture‑sensitive PEI polymer matrix via electrospinning to synchronize humidity perception and signal transduction. Phase‑field simulations and experiments reveal how the composition and topology of the coupled piezoelectric textiles modulate recognition, conversion, and component utilization, enabling the design of high‑sensitivity, fast‑response humidity sensors. STP textiles achieve 0.9 %/RH% sensitivity and 20‑s response, enabling wearable emotion, exercise, and stress monitoring while revealing a chemisorption‑coupled energy conversion mechanism that paves the way for autonomous, multifunctional flexible sensors.

Abstract

The performance of chemical sensors is dominated by the perception of the target molecules via sensitive materials and the conduction of sensing signals through transducers. However, sensing and transduction are spatially and temporally independent in most chemical sensors, which poses a challenge for device miniaturization and integration. Herein, we proposed a sensing-transducing coupled strategy by embedding the high piezoresponse Sm-PMN-PT ceramic (d33 = ∼1500 pC N-1) into a moisture-sensitive polyetherimide (PEI) polymer matrix via electrospinning to conjugate the humidity perception and signal transduction synchronously and sympatrically. Through phase-field simulation and experimental characterization, we reveal the principle of design of the composition and topological structure of sensing-transducing coupled piezoelectric (STP) textiles in order to modulate the recognition, conversion, and sensitive component utilization ratio of the prepared active humidity sensors, achieving high sensitivity (0.9%/RH%) and fast response (20 s) toward ambient moisture. The prepared STP textile can be worn on the human body to realize emotion recognition, exercise status monitoring, and physiological stress identification. This work offers unprecedented insights into the coupling mechanism between chemisorption-related interfacial state and energy conversion efficiency and opens up a new paradigm for developing autonomous, multifunctional and highly sensitive flexible chemical sensors.