Symmetry matters in graphene growth

Rice researchers find subtle interactions with substrate may lead to better control 

Graphene islands formed in two distinctly different shapes on separate grains of copper (colored in blue and red) grown simultaneously because the substrates' atomic lattices have different orientations, according to Rice University researchers. Image by Y. Hao/coloring by V. Artyukhov

What lies beneath growing islands of graphene is important to its properties, according to a new study led by Rice University.

Scientists at Rice analyzed patterns of graphene – a single-atom-thick sheet of carbon – grown in a furnace via chemical vapor deposition. They discovered that the geometric relationship between graphene and the substrate, the underlying material on which carbon assembles atom by atom, determines how the island shapes emerge. The study led by Rice theoretical physicist Boris Yakobson and postdoctoral researcher Vasilii Artyukhov shows how the crystalline arrangement of atoms in substrates commonly used in graphene growth, such as nickel or copper, controls how islands form. The results appear this week in Physical Review Letters.

- See more at: Rice News

The latest fashion: Graphene edges can be tailor-made

Rice University theory shows it should be possible to tune material’s properties

Graphene nanoribbons can be enticed to form favorable "reconstructed" edges by pulling them apart with the right force and at the right temperature, according to researchers at Rice University. The illustration shows the crack at the edge that begins the formation of five- and seven-atom pair under the right conditions. Illustration by ZiAng Zhang

Theoretical physicists at Rice University are living on the edge as they study the astounding properties of graphene. In a new study, they figure out how researchers can fracture graphene nanoribbons to get the edges they need for applications.

New research by Rice physicist Boris Yakobson and his colleagues shows it should be possible to control the edge properties of graphene nanoribbons by controlling the conditions under which the nanoribbons are pulled apart.

In the work, which appeared this month in the Royal Society of Chemistry journal Nanoscale, the Rice team used sophisticated computer modeling to show it’s possible to rip nanoribbons and get graphene with either pristine zigzag edges or what are called reconstructed zigzags.

- See more at: Rice News

Sinuous grain boundaries in graphene demystified

The January 21 issue of Adv. Funct. Mater. features on its back cover work on graphene grain boundaries

The image shows a simulated grain boundary stitching two graphene domains tilted at a 28° angle exhibits a well-defined sinuous shape, which is revealed to be energetically preferred. Such sinuous grain boundary, appeared to be a curved river on land, are highlighted by B. I. Yakobson and co-workers on page 367 as a new channel to explore novel electronic behavior in graphene and to reach the as yet unexplored flatlands of two-dimensional materials.

Advanced Materials is Owl about Rice

High-impact journal publishes centennial edition with broad overview of materials science at Rice

Materials scientists who received Volume 24, Issue 36 of the respected journal Advanced Materials recently may have noticed it contained Rice University research and nothing else.

That is no mistake. The journal published a special issue this fall focused on Rice, the home of a large number of materials researchers that has been recognized by a Times Higher Education survey as the best in the world.  more…

Graphene rips follow rules

A press release from Rice University Office of Public Affairs / News & Media Relations covers recent work by our group published in Nano Letters:

Rice University simulations show carbon sheets tear along energetically favorable lines

HOUSTON — (Jan. 5, 2012) — Research from Rice University and the University of California at Berkeley may give science and industry a new way to manipulate graphene, the wonder material expected to play a role in advanced electronic, mechanical and thermal applications.

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