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Title: Precise assembly and joining of silver nanowires in three dimensions for highly conductive composite structures

Three-dimensional (3D) electrically conductive micro/nanostructures are now a key component in a broad range of research and industry fields. In this work, a novel method is developed to realize metallic 3D micro/nanostructures with silver-thiol-acrylate composites via two-photon polymerization followed by femtosecond laser nanojoining. Complex 3D micro/nanoscale conductive structures have been successfully fabricated with ∼200 nm resolution. The loading of silver nanowires (AgNWs) and joining of junctions successfully enhance the electrical conductivity of the composites from insulating to 92.9 S m−1at room temperature. Moreover, for the first time, a reversible switching to a higher conductivity is observed, up to ∼105S m−1at 523 K. The temperature-dependent conductivity of the composite is analyzed following the variable range hopping and thermal activation models. The nanomaterial assembly and joining method demonstrated in this study pave a way towards a wide range of device applications, including 3D electronics, sensors, memristors, micro/nanoelectromechanical systems, and biomedical devices, etc.

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Publication Date:
Journal Name:
International Journal of Extreme Manufacturing
Page Range or eLocation-ID:
Article No. 025001
IOP Publishing
Sponsoring Org:
National Science Foundation
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