New material makes production of displays cheaper

Researchers at the Penn State Research Institute in the United States propose using transparent metal compounds as conductors in displays other than the now widely used indium-tin-oxide or ito.

In a paper in Nature Materials, the researchers propose using materials such as strontium vanadate, SrVO3, and calcium vanadate, CaVO3. Like ito, these materials are transparent in thin film form, but cost a fraction compared to ito. Indium in particular is a precious material. It is a by-product of tin, lead, iron and copper mining and is difficult to ‘separate’ from the waste generated during ore processing. With the current mining methods it is suspected that there is still about fourteen years of indium to be mined.

Despite the recurring promise of carbon nanotubes, which could also serve as transparent conductors, it is still difficult to produce them reliably on a large scale. In this paper, the researchers propose a material in which the electrostatic interaction between negatively charged electrons is very large compared to their kinetic energy, says Roman Engel-Herbert, one of the researchers. In these materials electrons ‘flow’ as in a liquid instead of bouncing around as in a gas.

A thin film of these materials is also transparent yet conductive enough. Now it is important to find out which materials have properties that are comparable to those of strontium vanadate and calcium vanadate. The costs of the various metals are many times lower than those of indium. Further research will have to show how the materials can be produced on a large scale.

Strontium Vanadate and Calcium Vanadate