Nanofibre etching makes superior transparent conductors
Today, the transparent conductors that function as electrodes in optoelectronic devices such as touch panel screens, liquid crystal displays, and solar cells are composed of indium tin oxide (ITO), which is brittle and expensive. With this in consideration, Japanese researchers came up with an approach to fabricate conductors using nanofibre—a material that may well be a viable alternative to ITO.
Hidetoshi Matsumoto, Masatoshi Tokita, Koichi Sakajiri, and graduate student Keisuke Azuma at Tokyo Institute of Technology used an electrospun polystyrene nanofibre mask template to carry out a simple wet chemical etching of aluminium(Al) metalised polymer films.
Micrograph of aluminium nanofibre networks fabricated on a poly(ethyleneterephthalate) film by wet chemical etching with an electrospun polymer nanofibre mask. Source: TIT
The resulting Al nanowire networks—with a width of 500nm and an area fraction of 22 per cent—exhibited 80 per cent optical transmittance and sheet resistance of 45Ωsq-1, figures of merit that are comparable to conventional transparent conductors. Notably, the fabrication method developed by the Tokyo Tech group is scalable for mass production and cost effective.
Flexible, unbreakable, and transparent, the fabricated electrodes show promise for applications in both large-scale and mobile optoelectronic devices including ones that are flexible. Examples of applications are large displays, large interactive touch screens, photovoltaic solar panels, light-emitting diode panels, smart phones, and tablets.
Flexible, unbreakable, and transparent electrodes with conductive nanofibre networks. Source: TIT