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Deformable energy devices capable of efficiently scavenging ubiquitous mechanical signals enable the realization of self-powered wearable electronic systems for emerging human-integrated technologies. Triboelectric nanogenerators (TENGs) utilizing soft polymers with embedded additives and engineered dielectric properties emerge as ideal candidates for such applications. However, the use of solid filler materials in the state-of-the-art TENGs limits the devices' mechanical deformability and long-term durability. The current structural design for TENGs faces the dilemma where the enhanced dielectric constant of the TENG's contact layer leads to an undesirable saturation of the surface charge density. Here, we present a novel scheme to address the above issues, by exploring a liquid-metal-inclusion based TENG (LMI-TENG) where inherently deformable core–shell LMIs are incorporated into wearable high-dielectric-constant polymers. Through a holistic approach integrating theoretical and experimental efforts, we identified the parameter space for designing an LMI-TENG with co-optimized output and mechanical deformability. As a proof of concept, we demonstrated an LMI-TENG based wireless media control system for a self-powered user interface. The device architecture and design scheme presented here provide a promising solution towards the realization of self-powered human-integrated technologies.
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This content will become publicly available on April 1, 2027
Integrated carbon nanotube-reinforced PTFE nanofiber membranes for breathable, super-hydrophobic, and thermally resilient triboelectric nanogenerators
Abstract The rapid advancement of self-powered wearable electronics has created an urgent demand for materials that can simultaneously enable efficient energy harvesting and reliable sensing while maintaining mechanical flexibility, breathability, and environmental robustness. Here, a carbon nanotube (CNT)-reinforced polytetrafluoroethylene (PTFE) nanofiber membrane with multiple functionalities is developed through an electrospinning-sintering strategy, integrating high breathability, super-hydrophobicity, and thermal resilience within a single architecture. The incorporation of CNTs enhances dielectric properties and mechanical strength, forming a robust charge-retentive fibrous network. The optimized membrane exhibits a super-hydrophobic surface with a water contact angle of 155.49°, along with excellent air permeability and outstanding thermal stability. When assembled into a triboelectric nanogenerator (TENG), the device delivers an open-circuit voltage of ~ 122 V, sufficient to power portable electronics. The TENG also demonstrates excellent fouling resistance and self-cleaning capability, maintaining stable performance after repeated contamination-washing cycles. Owing to its breathable and flexible configuration, the device enables real-time motion and respiration monitoring without compromising air exchange. It also exhibits consistent output under high-temperature (up to 250 °C) and underwater conditions, with the latter further showcased through Morse-code communication. This work establishes a scalable materials design strategy for multifunctional nanofibrous TENGs, offering a versatile platform for adaptive, self-powered electronic systems operable across diverse environments.
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- PAR ID:
- 10701978
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Advanced Composites and Hybrid Materials
- Volume:
- 9
- Issue:
- 2
- ISSN:
- 2522-0128
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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