Researchers use graphene flakes to make highly conductive ink.
A new type of high-quality ink has been developed by US researchers that uses graphene patterns for creating highly detailed and highly conductive electrodes, with the newest study of this type of ink having around 250 times the conductive property of previous patterns created.
Headed by Ethan B Sector of Northwestern University in Evanston, the study has resulted in the graphene inkjet being highly tolerant to the stresses brought through bending; only losing a small amount of conductivity.
Noting that inkjet printing is a useful method for handling components composed of electricity due to the cost-versus-range dynamic and the ability to print substrates, the researchers recognise that the printing of such highly conductive electrodes is challenging due to the high level of resolution required. However, graphene was chosen for its high conductivity, chemical stability and flexibility compared to alternative inks.
According to the researchers, one of the most important aspects of printing with the compound is the gathering of such large quantities of graphene; but while there are a handful of mass-production methods available, the inkjet printing comes with additional benefit of exfoliation – the use of graphene oxide to produce flakes.
Mark Hersam, a professor of Materials Science and Engineering at Northwestern University and co-author of the study, which was published in the Journal of Physical Chemistry Letters, said: “Essentially all electronic devices and circuits required high-conductivity and high-resolution electrical contacts and interconnects. Therefore, our graphene inks have the potential to impact a wide range of applications, especially printed electronics, flexible electronics, and affordable electronics. Example downstream applications for these types of electronic devices include smartphones, tablets, flat panel displays, and photovoltaics.”
Explaining how far the ink development has progressed so far and where it is heading, Hersam said: “Thus far, we have achieved the graphene ink development and characterization. On the other hand, our future research will focus on integrating our printed graphene inks into fully fabricated electronic devices and circuits, including the downstream applications listed above. In this manner, we can fully exploit our fundamental research advances for real-world technology.”