The INFINITY project, “Indium-free transparent conductive oxides for glass and plastic substrates”, focused on the development of novel inks for transparent conductive coatings (TCCs) that are used in a variety of optoelectronic devices including flat panel displays, photovoltaic cells, etc. Currently, indium tin oxide (ITO) is the most commonly used material for these applications; however indium is a scarce and expensive element. Therefore the main objective of the INFINITY project was to develop alternative indium-free oxide coatings with similar electrical conductivity and high optical transmission as ITO coatings, to deposit these coatings by a direct, cost-effective printing process.
Specifically, the INFINITY project has developed UV curable inks containing doped metal oxide (zinc and titanium oxides) nanoparticles. These novel inks have been modified and adapted to printing techniques such as gravure and ink-jet printing to enable direct writing of multi-layers and patterns, avoiding the waste associated with existing etch patterning processes. A novel laser-based approach was used for low-temperature sintering of the printed conductive coatings, thereby allowing for not only glass but also flexible substrates to be used.
The project has progressed TCC technology by allowing for ink formulations that facilitate the application of sol-gel based coatings at low temperatures, providing a conduit for the application of conductive coatings onto plastic without causing damage. This will allow for a wider variety of end-user applications, ranging from displays to solar panels to organic photovoltaics and energy harvesting by smart windows.
INFINITY was a 3-year research project funded by the EU Framework Programme for Research and Innovation: Horizon 2020, bringing together European experts from all aspects of the fabrication supply chain: EpiValence, Lurederra, TWI, INM, University of Hull, Belectric OPV and FlexEnable.
