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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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Multifunctional Mechanical Metamaterials with Embedded Triboelectric Nanogenerators
Abstract The flexibility of planar triboelectric nanogenerators (TENGs) enables them to be embedded into structures with complex geometries and to conform with any deformation of these structures. In return, the embedded TENGs function as either strain‐sensitive active sensors or energy harvesters while negligibly affecting the structure's original mechanical properties. This advantage inspires a new class of multifunctional materials where compliant TENGs are distributed into local operational units of mechanical metamaterial, dubbed TENG‐embedded mechanical metamaterials. This new class of metamaterial inherits the advantages of a traditional mechanical metamaterial, in that the deformation of the internal topology of material enables unusual mechanical properties. The concept is illustrated with experimental investigations and finite element simulations of prototypes based on two exemplar metamaterial geometries where functions of self‐powered sensing, energy harvesting, as well as the designated mechanical behavior are investigated. This work provides a new framework in producing multifunctional triboelectric devices.
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- Award ID(s):
- 1662925
- PAR ID:
- 10457494
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 30
- Issue:
- 23
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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