- About Us
- Career Center
- Nano-Social Network
- Nano Consulting
- My Account
Because of its intriguing properties graphene could be the ideal material for building new kinds of electronic devices such as sensors, screens, or even quantum computers.
One of the keys to exploiting graphene's potential is being able to create atomic-scale defects - where carbon atoms in its flat, honeycomb-like structure are rearranged or 'knocked out' - as these influence its electrical, chemical, magnetic, and mechanical properties.
A team led by Oxford University scientists report in Nature Communications a new approach to a new approach to engineering graphene's atomic structure with unprecedented precision.
'Current approaches for producing defects in graphene are either like a 'shotgun' where the entire sample is sprayed with high energy ions or electrons to cause widespread defects, or a chemistry approach where many regions of the graphene are chemically reacted,' said Jamie Warner from Oxford University's Department of Materials, a member of the team.
'Both methods lack any form of control in terms of spatial precision and also the defect type, but to date are the only reported methods known for defect creation.'
The new method replaces the 'shotgun' with something more like a sniper rifle: a minutely-controlled beam of electrons fired from an electron microscope.
'The shotgun approach is restricted to micron scale precision, which is roughly an area of 10,000,000 square nanometres, we demonstrated a precision to within 100 square nanometres, which is about four orders of magnitude better,' explains Alex Robertson of Oxford University's Department of Materials, another member of the team.
Yet it isn't just about the accuracy of a single 'shot'; the researchers also show that by controlling the length of time graphene is exposed to their focused beam of electrons they can control the size and type of defect created.
'Our study reveals for the first time that only a few types of defects are actually stable in graphene, with several defects being quenched by surface atoms or relaxing back to pristine by bond rotations,' Jamie tells me.
The ability to create just the right kind of stable defects in graphene's crystal structure is going to be vital if its properties are to be harnessed for applications such as mobile phones and flexible displays.
'Defect sites in graphene are much more chemically reactive, so we can use defects as a site for chemical functionalisation of the graphene. So we can attach certain molecules, such as biomolecules, to the graphene to act as a sensor,' Alex tells me.
'Defects in graphene can also give rise to localized electron spin, an attribute that has important future use in quantum nanotechnology and quantum computers.'
At the moment scaling up the team's technique into a manufacturing process to create graphene-based technologies is still a way off. Currently electron microscopes are the only systems that can achieve the necessary exquisite control of an electron beam.
But, Alex says, it is always possible that a scalable electron beam lithography type technique may be developed in the future that could allow for defect patterning in graphene.
And it's worth remembering that it wasn't so long ago that the technology needed to etch millions of transistors onto a tiny slice of silicon seemed like an impossible dream.
About University of Oxford
Oxford is the oldest university in the English-speaking world, and a leader in learning, teaching and research.
For more information, please click here
Press & Information Office
telephone:+44 01865 280528
Copyright © University of OxfordIf you have a comment, please Contact us.
Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
|Related News Press|
News and information
Display technology/LEDs/SS Lighting/OLEDs
Spain nanotechnology featured at NANO KOREA 2015 June 26th, 2015
The quantum middle man July 2nd, 2015
Producing spin-entangled electrons July 2nd, 2015
New conductive ink for electronic apparel June 25th, 2015
Leti to Present Solutions to New Applications Using 3D Technologies at SEMICON West LetiDay Event, July 14: Leti Experts also Will Speak at TechXPOT Session on MEMS and STS Session on Lithography Cost-and-Productivity Issues Below 14nm June 22nd, 2015