Self-encapsulated ionic fibers based on stress-induced adaptive phase transition for non-contact depth-of-field camouflage sensing

Abstract

Ionically conductive fibers have promising applications; however, complex processing techniques and poor stability limit their practicality. To overcome these challenges, we proposed a stress-induced adaptive phase transition strategy to conveniently fabricate self-encapsulated hydrogel-based ionically conductive fibers (se-HICFs). se-HICFs can be produced simply by directly stretching ionic hydrogels with ultra-stretchable networks (us-IHs) or by dip-drawing from molten us-IHs. During this process, stress facilitated the directional migration and evaporation of water molecules in us-IHs, causing a phase transition in the surface layer of ionic fibers to achieve self-encapsulation. The resulting sheath-core structure of se-HICFs enhanced mechanical strength and stability while endowing se-HICFs with powerful non-contact electrostatic induction capabilities. Mimicking nature, se-HICFs were woven into spider web structures and camouflaged in wild environments to achieve high spatiotemporal resolution 3D depth-of-field sensing for different moving media. This work opens up a convenient route to fabricate stable functionalized ionic fibers.

Phase-Directed Assembly of Triboelectric Nanopaper for Self-Powered Noncontact Sensing

“…The rapidly advancing wearable technology is revolutionizing the way people communicate with each other and their surroundings, accelerating the integration of our lives into the intelligent information network of the Internet of Things (IoT), and serving as a driving force for continuous innovation in fields such as smart cities, digital twins, and precision medicine. − To unleash the immense potential of wearable sensing in diverse domains, noncontact wearable sensing technologies based on wireless interactions such as ultrasound, lidar, and infrared are emerging as a new trend, paving the way for a more secure and efficient wearable human-machine interaction perception network in the era of the Internet of Everything (IoE). − However, most current noncontact wearable sensors rely on external power sources, , posing a technical challenge to power the vast and growing array of noncontact sensing nodes in the IoT . Recently, triboelectric nanogenerators (TENGs) technology, based on the principles of contact electrification and electrostatic induction, has been demonstrated to seamlessly integrate energy harvesting and sensing detection in noncontact mode, offering a solution to the sustainable development challenges of noncontact sensing technologies. − …”