Rice University has developed graphene-based electrodes making flexible, transparent electronics possible in reality. The laboratory led by James Tour, Rice University chemist, has formed thin films that enhance LED lighting, solar panels, and touch-screen displays.
A hybrid material that combines a fine aluminum mesh with a single-atom-thick layer of graphene outperforms materials common to current touch screens and solar cells. The transparent, flexible electrodes were developed in the lab of Rice University chemist James Tour. (Credit: Yu Zhu/Rice University)
The hybrid graphene film developed in the lab is a robust material for replacing indium tin oxide (ITO), a product chiefly utilized in the form of conductive transparent coating. ITO plays a vital role in most of the flat-panel displays such as touch screens on iPads and phones. It is also used in solar cells and organic light-emitting diodes (OLEDs). However, ITO employed in these applications has several limitations.
The thin film developed in Tour’s lab integrates a highly conductive, single-layer graphene sheet with a metal nanowire grid. The researchers ascertain that this material features low resistance to electricity and better transparency.
Postdoctoral researcher, Yu Zhu, lead author of this research paper, stated that fine meshes of metal display good conductivity, yet the gaps found in the nanowires for providing transparency make them unfit to be used as a stand-alone material in conductive electrodes. However, combination of the materials with graphene provides excellent results. Graphene occupies all the empty spaces of the metal grid; in turn, graphene is strengthened by the metal grid.
The researchers discovered a grid of nanowires measuring 5 ìm using low cost, light-weight aluminum without affecting the transparency of the material. Tour stated that it is easy to produce metal grids on a flexible surface through standard methods such as ink-jet and roll-to-roll printing.