Multifunctional metamaterials (MFMs) capable of energy harvesting and vibration control are particularly attractive for smart structures, wearable/biointegrated electronics, and intelligent robotics. Here, a novel MFM based on triboelectric nanogenerators (TENGs), which can harvest environmental energy and reduce vibration simultaneously, is reported. The unit cells of the MFM consist of a local resonator, an integrated contact‐ separation mode TENG, and spiral‐shaped connecting beams. A multiphysics theoretical model is developed for quantitatively evaluating the performance of the MFM by including the mechanical and electrical fields interactions, which is further validated by experimental testing. It is demonstrated that the TENG‐based MFM can not only effectively harvest vibration energy to power electronics but also dramatically suppress low‐frequency mechanical vibration. This work provides a new design and model for developing novel TENG‐based MFMs for advanced smart systems used in a variety of applications.
Progress in soft and stretchable electronics depends on energy sources that are mechanically compliant, elastically deformable, and renewable. Energy harvesting using triboelectric nanogenerators (TENGs) made from soft materials provides a promising approach to address this critical need. Here, an elastomeric composite is introduced with sedimented liquid metal (LM) droplets for TENG‐based energy harvesting that relies on assembly of the LM to form phase‐separated conductive and insulating regions. The sedimented LM elastomer TENG (SLM‐TENG) exhibits ultrahigh stretchability (strain limit
- PAR ID:
- 10455260
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 5
- Issue:
- 11
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Ongoing efforts in triboelectric nanogenerators (TENGs) focus on enhancing power generation, but obstacles concerning the economical and cost‐effective production of TENGs continue to prevail. Micro‐/nanostructure engineering of polymer surfaces has been dominantly utilized for boosting the contact triboelectrification, with deposited metal electrodes for collecting the scavenged energy. Nevertheless, this state‐of‐the‐art approach is limited by the vague potential for producing 3D hierarchical surface structures with conformable coverage of high‐quality metal. Laser‐shock imprinting (LSI) is emerging as a potentially scalable approach for directly surface patterning of a wide range of metals with 3D nanoscale structures by design, benefiting from the ultrahigh‐strain‐rate forming process. Here, a TENG device is demonstrated with LSI‐processed biomimetic hierarchically structured metal electrodes for efficient harvesting of water‐drop energy in the environment. Mimicking and transferring hierarchical microstructures from natural templates, such as leaves, into these water‐TENG devices is effective regarding repelling water drops from the device surface, since surface hydrophobicity from these biomicrostructures maximizes the TENG output. Among various leaves' microstructures, hierarchical microstructures from dried bamboo leaves are preferable regarding maximizing power output, which is attributed to their unique structures, containing both dense nanostructures and microscale features, compared with other types of leaves. Also, the triboelectric output is significantly improved by closely mimicking the hydrophobic nature of the leaves in the LSI‐processed metal surface after functionalizing it with low‐surface‐energy self‐assembled‐monolayers. The approach opens doors to new manufacturable TENG technologies for economically feasible and ecologically friendly production of functional devices with directly patterned 3D biomimic metallic surfaces in energy, electronics, and sensor applications.
