Printed transistors from 2D materials may lead to smart packaging

Imagine a milk carton sending you an alert on smartphone when its content is about to go out-of-date. This could soon be possible, thanks to the researchers who have fabricated for the first time printed transistors consisting entirely of two-dimensional nano-materials.

The team used standard printing techniques to combine graphene nano-sheets 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-nano-sheet, working transistor.

This study, published in the journal Science, 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, the researchers said.

The research could thus 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.

"In the future, printed devices will be incorporated into even the most mundane objects such as labels, posters and packaging," said lead researcher Jonathan Coleman, an investigator in AMBER, the materials science research centre hosted in Trinity College, Dublin, Ireland.

"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transmit information: for example, milk cartons could send messages to your phone warning that the milk is about to go out-of-date," Coleman added.

These 2D materials combine electronic properties with the potential for low-cost production.

"We believe that 2D nano-materials can compete with the materials currently used for printed electronics. Compared to other materials employed in this field, our 2D nano-materials have the capability to yield more cost effective and higher performance printed devices," Coleman said.

The research shows that conducting, semiconducting and insulating 2D nano-materials 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 nano-sheets," Coleman said.

--IANS

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