Smart Printed Electronics

Researchers in AMBER, the materials science research centre hosted in Trinity College Dublin, have fabricated printed transistors consisting entirely of 2-dimensional nanomaterials for the first time. These 2D materials combine exciting electronic properties with the potential for low-cost production. This breakthrough could unlock the potential for applications such as food packaging that displays a digital countdown to warn you of spoiling, wine labels that alert you when your white wine is at its optimum temperature, or even a window pane that shows the day’s forecast

This discovery opens the path for industry, such as ICT and pharmaceutical, to cheaply print a host of electronic devices from solar cells to LEDs with applications from interactive smart food and drug labels to next-generation banknote security and e-passports.

printed transistor

Prof Jonathan Coleman, who is an investigator in AMBER and Trinity’s School of Physics, said, “In the future, printed devices will be incorporated into even the most mundane objects such as labels, posters and packaging.
Printed electronic circuitry (constructed from the devices we have created) will allow consumer products to gather, process, display and transmit information: for example, milk cartons could send messages to your phone warning that the milk is about to go out-of-date.

We believe that 2D nanomaterials can compete with the materials currently used for printed electronics. Compared to other materials employed in this field, our 2D nanomaterials have the capability to yield more cost effective and higher performance printed devices. However, while the last decade has underlined the potential of 2D materials for a range of electronic applications, only the first steps have been taken to demonstrate their worth in printed electronics. This publication is important because it shows that conducting, semiconducting and insulating 2D nanomaterials can be combined together in complex devices. We felt that it was critically important to focus on printing transistors as they are the electric switches at the heart of modern computing. We believe this work opens the way to print a whole host of devices solely from 2D nanosheets.”
Led by Prof Coleman, in collaboration with the groups of Prof Georg Duesberg (AMBER) and Prof. Laurens Siebbeles (TU Delft, Netherlands), the team used standard printing techniques to combine graphene nanosheets as the electrodes with two other nanomaterials, tungsten diselenide and boron nitride as the channel and separator (two important parts of a transistor) to form an all-printed, all-nanosheet, working transistor.

The AMBER team’s findings have been published today in the journal Science*.


Mimicking The Neural Networks Of The Human Brain

Researchers at the Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) at Trinity College in Dublin – Ireland – are pursuing a new nanomaterial-based approach to neural networks that combines work in nanowires and memristors (2-terminal memory devices based on resistance switching effects). They develop a new computing paradigm that mimics the neural networks of the human brain. Both nanowires and memristors are part of the history of research into neural networks and artificial intelligence (AI). Researchers have been investigating the use of nanowires in building electronic meshes on which nerve tissues can be grown; the mesh, they hope, could link nerve cells with electronics. And almost from the time memristors were first isolated and characterized, researchers have been looking at using them in chips that would lead to artificial intelligence.
Professor John Boland, director of CRANN, and his colleagues will be using the research grant to build on their previous work. They already discovered that when electricity—or other stimuli such as chemicals or light—is applied to a random network of nanowires, it generates a chemical reactions at the junctions where the nanowires cross over each other.

nanowire network
This phenomenon is similar to the way the brain works, in that there are bundles of nerves that cross over one another, forming junctions. Over time, the human brain begins to learn which of these junctions is important and discards the rest.

Nanomaterials in a Heart Beat

Heart disease is the leading cause of death. Once damaged by heart attack, cardiac muscle has very little capacity for self-repair and at present there are no clinical treatments available to repair damaged cardiac muscle tissue. Over the last 10 years, there has been tremendous interest in developing a cell-based therapy to address this problem. Since the use of a patient’s own heart cells is not a viable clinical option, many researchers are working to try to find an alternative source of cells that could be used for cardiac tissue repair. Stem cell scientists have capitalised on the electrical properties of a widely used nanomaterial to develop cells which may allow the regeneration of cardiac cells. The breakthrough has been led by a team of scientists at the Regenerative Medicine Institute (REMEDI) at the National University of Ireland Galway in conjunction with Trinity College Dublin.

The electrical properties of the nanomaterial triggered a response in the mesenchymal (adult) stem cells, which we sourced from human bone marrow. In effect, they became electrified, which made them morph into more cardiac-like cells”, explains Valerie Barron of REMEDI at National University of Ireland Galway. “This is a totally new approach and provides a ready-source of tailored cells, which have the potential to be used as a new clinical therapy. Excitingly, this symbiotic strategy lays the foundation stone for other electroactive tissue repair applications, and can be readily exploited for other clinically challenging areas such as in the brain and the spinal cord.