A novel electrode architecture has led to a new way to make transparent electrical contacts. Typical ways of attaching a conductor to a non-metallic material allow you to see the electrode. However, for many applications, like light emitting diode (LED) displays, smart windows and solar cells, transparency to visible light is a requirement that conflicts with electrical conductance. Thinner films are more transparent, but less conductive. The new architecture consists of specially patterned nanoscale-thick metallic ribbons, standing on edge, supported by a polymer matrix. Because the ribbons are only about 40 nanometers wide, light can pass between them, but their height provides enough material to ensure high conductivity. The conductivity and transmittance of the new structure rival currently used indium-tin-oxide transparent electrodes, is less brittle, and will enable flexible, large area applications. It provides an alternative to using indium, which has been identified as an “energy critical element”.
A New Architecture for Transparent Electrodes: Relieving the Trade-Off between Electrical Conductivity and Optical Transmittance