The presence of a transparent and conducting electrode is a prerequisite for LEDs, photovoltaic cells, e-paper or for transparent displays. Indium tin oxide is currently used, but it is costly and sources are limited. Roland Hany and colleagues, Swiss Federal Laboratories for Material Science, Switzerland, have woven metal and polymer fibers into a mesh as a basis for a non-indium based electrode.
The meshes were then immersed in a liquid polymer film to fill the open spaces in the mesh with an inert polymer. This reduces the distance between the exposed metal wires, allowing more complete and thinner coverage of the conducting poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonic acid) (PEDOT:PSS) films.
A roll-to-roll process running at speeds of 10 m per minute permits the production of large transparent electrodes for low cost organic electronics.
Image: Schematic side view of an organic solar cell and a roll of woven precision fabric (1 m wide, 100 meters long). (c) Wiley-VCH
- Woven Electrodes for Flexible Organic Photovoltaic Cells
W. Kylberg, F. A. de Castro, P. Chabrecek, U. Sonderegger, B. T.-T. Chu, F. Nüesch, R. Hany,
Adv. Mater. 2011.