Making plastic more transparent while adding electrical conductivity

(Image of Jay Guo holding a sheet of clear conductor on the College of Engineering North Campus. Through it, a lamp and tall building are visible.) — Jay Guo holds a sheet of flexible transparent conductor on the University of Michigan’s College of Engineering North Campus. (Photo courtesy of Robert Coelius/Michigan Engineering)

In an effort to improve large touchscreens, LED light panels and window-mounted infrared solar cells, a team of researchers at U-M has made plastic conductive while also making it more transparent.

They provide a recipe to help other researchers find the best balance between conductivity and transparency by creating a three-layer anti-reflection surface. The conductive metal layer is sandwiched between two “dielectric” materials that allow light to pass through easily. The dielectrics reduce the reflection from both the plastic and metal layer between them.

“We developed a way to make coatings with high transparency and conductivity, low haze, excellent flexibility, easy fabrication and great compatibility with different surfaces,” said Jay Guo, a professor of electrical engineering and computer science at U-M, who led the work.

The paper, published in Nature Communications, is titled, “Ultrathin-metal-film-based transparent electrodes with relative transmittance surpassing 100%.”