posted on 2017-01-17, 00:00authored byYuan Liu, Jianming Zhang, Heng Gao, Yan Wang, Qingxian Liu, Siya Huang, Chuan Fei Guo, Zhifeng Ren
Silver
nanowire (AgNW) films have been studied as the most promising
flexible transparent electrodes for flexible photoelectronics. The
wire–wire junction resistance in the AgNW film is a critical
parameter to the electrical performance, and several techniques of
nanowelding or soldering have been reported to reduce the wire–wire
junction resistance. However, these methods require either specific
facilities, or additional materials as the “solder”,
and often have adverse effects to the AgNW film or substrate. In this
study, we show that at the nanoscale, capillary force is a powerful
driving force that can effectively cause self-limited cold welding
of the wire–wire junction for AgNWs. The capillary-force-induced
welding can be simply achieved by applying moisture on the AgNW film,
without any technical support like the addition of materials or the
use of specific facilities. The moisture-treated AgNW films exhibit
a significant decrease in sheet resistance, but negligible changes
in transparency. We have also demonstrated that this method is effective
to heal damaged AgNW films of wearable electronics and can be conveniently
performed not only indoors but also outdoors where technical support
is often unavailable. The capillary-force-based method may also be
useful in the welding of other metal NWs, the fabrication of nanostructures,
and smart assemblies for versatile flexible optoelectronic applications.