Flexible, multifunctional sensor based on core-sheath sensing medium for humidity sensing and heat-resistant pressure.

The practical implementation of wearable sensing devices for human health monitoring requires significant advancements in lightweight design and multifunctional integration. Fiber-shaped sensors have attracted considerable research attention due to their ability to maintain exceptional sensitivity and measurement accuracy under various mechanical deformations, including bending, stretching, and torsion. Nevertheless, the functional integration remains constrained, particularly as evidenced by sensitivity degradation and device failure under extreme high-temperature conditions, which severely hinders their practical applicability for real-time health monitoring applications in complex environmental scenarios. Herein, we developed a core-sheath aerogel fibrous multifunctional sensor via a one-step coaxial wet-spinning technique. This sensor integrates humidity sensing capabilities for respiratory monitoring and liquid molecule recognition, along with high-temperature-resistant pressure sensing performance. The fiber-based humidity sensor demonstrates rapid response and ultrahigh sensitivity (3144.74 %/% RH) with excellent repeatability. Beyond enabling real-time respiratory detection, the ANFs@MXene/PVA (AMP) humidity sensor responds effectively to non-contact humidity stimuli and discriminates diverse liquid molecules, showcasing its potential for both contact and non-contact environmental sensing in complex scenarios. Additionally, the aramid nanofiber-based sheath enhances the stability of the fiber sensor as a wearable electronic device under extreme conditions, ensuring its functionality in high-temperature environments. This intelligent core-sheath fiber architecture offers a robust solution for real-time health monitoring in harsh environments, demonstrating significant potential for applications in smart textiles.