© daveynin
© daveynin

Graphene key to growing 2D materials

Materials scientists from Pennsylvania State University, US, have discovered a method for making 2D materials that could lead to new properties in nitrides.

This first growth of two-dimensional gallium nitride using graphene encapsulation could lead to applications in deep ultraviolet lasers, next-generation electronics and sensors.

Associate professor of materials science and engineering Joshua Robinson said: “These experimental results open up new avenues of research in 2D materials.

“This work focuses on making 2D gallium nitride, which has never been done before.”

Gallium nitride in its three-dimensional form is known to be a wide-bandgap semiconductor. When grown in its two-dimensional form, it transforms into an ultrawide-bandgap material, tripling the energy spectrum it can operate in, including the whole ultraviolet, visible and infrared spectra.

This work will have a particular impact on electro-optic devices that manipulate and transmit light.

Zak Al Balushi, a PhD candidate co-advised by Robinson and Dr Joan Redwing, said: “We have to synthesise materials that do not exist in nature. Typically, new material systems are highly unstable. But our growth method, called Migration Enhanced Encapsulated Growth (MEEG), uses a layer of graphene to assist the growth and stabilise a robust structure of 2D gallium nitride.”

Robinson believes that in the case of two-dimensional gallium nitride, the addition of a layer of graphene will make all the difference.

Graphene, a one-atom-thick layer of carbon atoms, is known for its electronic properties and strength and is supported by Horizon 2020, the EU Framework Programme for Research and Innovation.