Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Flat boron by the numbers

01.02.2013
Rice University researchers calculate what it would take to make new two-dimensional material
It would be a terrible thing if laboratories striving to grow graphene from carbon atoms kept winding up with big pesky diamonds.

“That would be trouble, cleaning out the diamonds so you could do some real work,” said Rice University theoretical physicist Boris Yakobson, chuckling at the absurd image.

Yet something like that keeps happening to experimentalists working to grow two-dimensional boron. Boron atoms have a strong preference to clump into three-dimensional shapes rather than assemble into pristine single-atom sheets, like carbon does when it becomes graphene. And boron clumps aren’t nearly as sparkly.

Yakobson and his Rice colleagues have made progress toward 2-D boron through theoretical work that suggests the most practical ways to make the material and put it to work. Earlier calculations by the group indicated 2-D born would conduct electricity better than graphene.

Through first-principle calculations of the interaction of boron atoms with various substrates, the team came up with several possible paths experimentalists may take toward 2-D boron. Yakobson feels the work may point the way toward other useful two-dimensional materials.

The Rice team’s results appear this week in the journal Angewandte Chemie International Edition. Rice graduate student Yuanyue Liu and research scientist Evgeni Penev are co-authors of the paper.

Yakobson’s lab first reported in a Nano Letters paper last year that unlike graphene, 2-D boron rolled into a nanotube would always be metallic. Also unlike graphene, the atomic arrangement can change without changing the nature of the material. Instead of the steady rank-and-file of hexagons in a perfect graphene sheet, 2-D boron consists of triangles. But boron could have vacancies – missing atoms – without affecting its properties.

That’s the theory. The problem that remains is how to make the stuff.

“We are, perhaps, so close,” Penev said. “Here we have conceived a material that resembles graphene, but is always conductive no matter what form it takes. What we’re doing now is exploring different possibilities to connect our theories with reality.”

The best method, they calculated, might be to feed boron into a furnace with silver or gold substrates in a process called chemical vapor deposition, commonly used to make graphene. The substrate is important, Penev said, because the atoms have to spill onto the surface and stick, but not too strongly.

“You have to have a substrate that doesn’t want to dissolve boron,” he said. “On the other hand, you want a substrate that doesn’t bind too strongly. You should be able to detach the boron layer.”

Then, like graphene, these atom-thick boron sheets could be applied to other surfaces for testing and, ultimately, for use in applications.

The study also calculated methods for creating sheets via saturation of boron atoms on the surface of boride substrates, and the evaporation of metal atoms from metal borides that leaves just the target atoms in a sheet.

“There are a lot of reasons boron could be interesting,” said Liu, the paper’s first author. “Boron is carbon’s neighbor on the periodic table, with one less electron, which might bring in lots of new physics and chemistry, especially on the nanoscale. For example, 2-D boron is more conductive than graphene because of its unique electronic structure and atomic arrangement.

“In fact, comparing (boron) with graphene is very helpful,” he said. “The state-of-art synthesis methods for graphene provide us good templates to explore 2-D boron synthesis.”

Yakobson is thinking a step beyond the current work. “There are many groups, at Rice and elsewhere, working on 2-D boron,” he said. “To appreciate this work, you have to stand back and contrast it with graphene; in some sense, the synthesis of graphene is trivial.

“Why? Because graphene is a God-given material,” he said. “It forms at the global minimum (energy) for carbon atoms – they go there willingly. But boron is a different story. It does not have a planar form as a global minimum, which makes it a really subtle problem. The novelty in this work is that we’re trying to trick it into building a two-dimensional motif instead of three.”

The search for 2-D materials with varying qualities is hot right now; another new paper from Rice on a hybrid graphene-hexagonal boron nitride shows the need for a 2-D semiconductor to complement the material’s conducting and insulating elements.

Yakobson hopes his study serves as a guideline for practical routes to other novel materials. “Now that there is a growing interest in a variety of 2-D materials, this may be a template,” he said.

Yakobson is Rice’s Karl F. Hasselmann Professor of Mechanical Engineering and Materials Science and professor of chemistry.

The Department of Energy (DOE) supported the research. Computations were performed on the National Science Foundation-funded Data Analysis and Visualization Cyberinfrastructure at Rice, along with resources at the National Institute for Computational Sciences and the DOE’s National Energy Research Scientific Computing Center.
Read the abstract at http://dx.doi.org/10.1002/anie.201207972

This news release can be found online at
http://news.rice.edu/2013/01/31/flat-boron-by-the-numbers/


Related Materials:

Yakobson Research Group:
http://biygroup.blogs.rice.edu/archives/category/group-news


Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation’s top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,708 undergraduates and 2,374 graduate students, Rice’s undergraduate student-to-faculty ratio is 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice has been ranked No. 1 for best quality of life multiple times by the Princeton Review and No. 2 for “best value” among private universities by Kiplinger’s Personal Finance. To read “What they’re saying about Rice,” go to http://tinyurl.com/AboutRiceU.

David Ruth | EurekAlert!
Further information:
http://www.rice.edu

Further reports about: 2-D pictures Flat Terrain big pesky diamonds boron atoms graphene hexagons

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

Im Focus: Researchers develop method to transfer entire 2D circuits to any smooth surface

What if a sensor sensing a thing could be part of the thing itself? Rice University engineers believe they have a two-dimensional solution to do just that.

Rice engineers led by materials scientists Pulickel Ajayan and Jun Lou have developed a method to make atom-flat sensors that seamlessly integrate with devices...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

UNLV study unlocks clues to how planets form

13.12.2018 | Physics and Astronomy

Live from the ocean research vessel Atlantis

13.12.2018 | Earth Sciences

Stanford researcher deciphers flows that help bacteria feed and organize biofilms

13.12.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>