Researchers at the University of Chicago have developed a new OLED display that can be stretched to more than twice its length while still maintaining a clear image.
“One of the most important components of nearly every consumer electronic we use today is a display, and we’ve combined knowledge from many different fields to create an entirely new display technology,” said Sihong Wang, assistant professor of molecular engineering, who led the research with Juan de Pablo, Liew Family Professor of Molecular Engineering.
“This is the class of material you need to finally be able to develop truly flexible screens,” added de Pablo. “This work is really foundational and I expect it to allow many technologies that we haven’t even thought of yet.”
“The materials currently used in these state-of-the-art OLED displays are very brittle; they don’t have any stretchability,” said Sihong Wang, co-corresponding author of the study. “Our goal was to create something that maintained the electroluminescence of OLED but with stretchable polymers.”
Researchers at the Pritzker School of Molecular Engineering at the University of Chicago, led by Sihong Wang (above) and Juan de Pablo>
Photo by John Zich/University of Chicago
The only way to develop an OLED capable of stretching would be with some molecular manipulation. Using computational predictions to develop its new OLED polymers and testing several prototypes, the researchers used thermally activated delayed fluorescence (TADF), a highly efficient way of allowing organic material to convert electricity into light.
By embedding alkyls – organic chemicals that contain only carbon and hydrogen atoms arranged in chains – in the polymer between TADF units, softness and flexibility were enhanced. The newly designed OLED could be stretched to more than twice its original length without disrupting its light-emitting abilities or display of a clear image.
“We have been able to develop atomic models of the new polymers of interest and, with these models, we simulated what happens to these molecules when you pull on them and try to bend them,” said Juan de Pablo, co-corresponding author of the study. “Now that we understand these properties at a molecular level, we have a framework to engineer new materials where flexibility and luminescence are optimised.”
top image: Photo courtesy of Wang Group