Source: University of Tennessee | David Goddard / Release | December 28, 2015
Whether at home, work, or play, touchscreen devices have quickly become one of the hallmarks of the modern world.
Phones, tablets, computers, and even televisions use the technology, which relies on substances known as transparent conductive films. All but a small fraction of those films are made from a particular class of oxides that, although they do the job very effectively, contain rare and costly elements.
Now, thanks to a breakthrough led by UT’s College of Engineering and Oak Ridge National Laboratory, that problem could soon be in the past.
“The electronics industry relies heavily on the use of Indium metal for the many situations requiring the right balance of transparency and current carrying ability,” said UT Professor Ramki Kalyanaraman. “While Indium is scarce, our new material contains elements that are far more abundant such as iron, terbium, and dysprosium.”
Kalyanaraman—who teaches both materials science and engineering as well as chemical and biomolecular engineering—explained that even though terbium and dysprosium are classified as rare earth elements, they are both more than ten times more abundant than Indium, providing reduced cost of material and processing.
That breakthrough earned the team a spot in the Nature journal Scientific Reports, highlighting the importance of the work and how it challenged previous understanding of such materials.
The team included faculty and students from UT as well as ORNL’s Quantum Information Science Group and Center for Nanophase Materials Sciences and the joint UT-ORNL Bredesen Center for Interdisciplinary Research and Graduate Education.
Kalyanaraman said their next step is to continue to explore combining transparency and conductivity, which are both key considerations for adaptation in devices and gadgets.
“Displays such as flat-screen TVs and touchscreens on computers, laptops, and phones can all benefit from our work, but being able to replace current technology with this new material goes beyond just those conveniences,” said Kalyanaraman. “Solar panels, smart windows, anything that relies on both of those properties (conductivity and transparency) stands to be improved.”
Like many breakthroughs, the advancement came as a result of an unintended occurrence.
The team was working on an alloy developed by the Naval Ordinance Lab more than thirty years ago, tinkering with how magnetism and optics interacted, when they synthesized a film from the material.
“We discovered that rather than being reflective like a metal should be, it was actually transparent,” said Kalyanaraman. “That began our exploration and eventual discovery that got us to the stage we are in today.”
Kalyanaraman said the material is likely three to five years away from commercial use.