Indium tin oxide (ITO) has been critical to the development and success of flat panel displays over the past decade and is expected by many to be a key component in the continuing development of high efficiency solar cells. However, a new technology under development by Duke chemist Ben Wiley may displace ITO and, consequently, have a significant impact on indium markets.
The research, outlined in the August 24th issue of Advanced Materials shows that copper nanowires produced in water can form long, thin, non-clumping wires, which can be used to manufacture transparent films that have the same properties as ITO films, but would be significantly cheaper to produce. The copper nanowires have also shown to be more durable than their counterpart, able to withstand repeated bending while retaining conductivity.
The demand for ITO for use in flat screen TVs, smart phones and solar cells has led the price of indium from around $ 150 per kilogram in 2000 to highs above $ 1000 per kilogram in 2005. Currently, indium metal prices are around US$ 650 per kilogram.By contrast, copper prices, while historically high, are only about US$ 9 per kilogram.
A new flexible, transparent film made from copper nanowires could compete with thin films produced using ITO. Image c/o Ben Wiley, Duke University