Each silver nanowire particle measures 20 microns long, meaning that if four nanowires were placed end-to-end, they would span the width of a human hair. The diameter of the nanowire is a thousand times smaller, which is also smaller than the wavelength of visible light, thus minimizing light scattering.
The silver nanoparticle wires are suspended in water and then applied onto surfaces using a de Laval jet nozzle at 400 metres (1312 feet) per second. The kinetic energy applying the nanowires to the surface is converted into heat, which causes the nanowires to fuse with one another. Alexander Yarin, one of the researchers who led this project, has stated that 400 meters per second is “ideal” since 600 metres per second would cut the wires, while the wires would fail to fuse at 200 metres per second.
The result of this process is a film with glass-like transparency and electrical conductivity comparable to silver plate. One can apply the film to a diverse range of surfaces, including three-dimensional objects of any shape and even surfaces meant for bending and stretching. In fact, the film was stretched seven times its original length and continued working.
The ultrathin film was developed by two collaborating teams of nanomaterials researchers from the University of Illinois at Chicago (UIC) and the Korea University in Seoul. Alexander Yarin and Sam Yoon led the effort in the U.S. and South Korea, respectively.
The research is published in the journal Advanced Functional Materials.
The Yarin-Yoon team developed a similar solution earlier in 2016 by electroplating a mat of nano-fiber with copper. However, Yarin has claimed that the self-fused silver nanowire film is easier to scale for high-volume production, thus making it much more suitable for commercial applications, such as wearable consumer electronics, among others.
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