An international team of scientists is developing an inkable nanomaterial that they say could one day become a spray-on electronic component for ultra-thin, lightweight, and bendable displays and devices.
The material, zinc oxide, could be incorporated into many components of future technologies including mobile phones and computers, thanks to its versatility and recent advances in nanotechnology, according to the team.
RMIT University’s Associate Professor Enrico Della Gaspera and Dr. Joel van Embden led a team of global experts to review production strategies, capabilities, and potential applications of zinc oxide nanocrystals in the journal Chemical Reviews.
“Progress in nanotechnology has enabled us to greatly improve and adapt the properties and performances of zinc oxide by making it super small, and with well-defined features,” said Della Gaspera, from the School of Science.
“Tiny and versatile particles of zinc oxide can now be prepared with exceptional control of their size, shape and chemical composition at the nanoscale,” said van Embden, also from the School of Science. “This all leads to precise control of the resulting properties for countless applications in optics, electronics, energy, sensing technologies and even microbial decontamination.”
The nanocrystals can be formulated into ink and deposited as an ultra-thin coating. The process is like ink-jet printing or airbrush painting, but the coating is hundreds to thousands of times thinner than a conventional paint layer.
“These coatings can be made highly transparent to visible light, yet also highly electrically conductive — two fundamental characteristics needed for making touchscreen displays,” Della Gaspera said.
The nanocrystals can also be deposited at low temperature, allowing coatings on flexible substrates, such as plastic, that are resilient to flexing and bending, the team says.
The team is ready to work with industry to explore potential applications using their techniques to make these nanomaterial coatings.
“Scalability is a challenge for all types of nanomaterials, zinc oxide included,” he said.
“Being able to recreate the same conditions that we achieve in the laboratory, but with much larger reactions, requires both adapting the type of chemistry used and engineering innovations in the reaction setup.”
In addition to these scalability challenges, the team needs to address the shortfall in electrical conductivity that nanocrystal coatings have when compared to industrial benchmarks, which rely on more complex physical depositions.
The intrinsic structure of the nanocrystal coatings, which enables more flexibility, limits the ability of the coating to conduct electricity efficiently.
“We and other scientists around the world are working toward addressing these challenges and good progress is being made,” Della Gaspera said.