Professor Karen Winey said that there are two problems with ITO; indium is relatively rare, so its cost and availability are erratic, and, more importantly for flexible devices, it's brittle.
Meanwhile, metal nanowires are increasingly inexpensive to make and deposit; they are suspended in a liquid and can easily be painted or sprayed onto a flexible or rigid substrate, rather than grown in vacuum as is the case for ITO.
The Penn team's simulation provides further evidence for each variable's role in the overall network's performance, helping the researchers home in on the right balance of traits for specific applications. Increasing the coverage area of nanowires, for example, always decreases the overall electrical resistance, but it also decreases optical transparency; as more and more nanowires are piled on the networks appear gray, rather than transparent.
The study was published in the journal ACS Nano.