Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Flat boron may take many forms: Rice University researchers find two-dimensional boron has potential advantages over graphene

Rice University researchers led by theoretical physicist BorisYakobson used a technique usually applied to alloys to explore the rich variety of two-dimensional boron. They treated the vacancies in boron like the holes in Swiss cheese, as an element essential to its existance. (Credit: Evgeni Penev/Rice University)
Rice University researchers led by theoretical physicist BorisYakobson used a technique usually applied to alloys to explore the rich variety of two-dimensional boron. They treated the vacancies in boron like the holes in Swiss cheese, as an element essential to its existance.

(Credit: Evgeni Penev/Rice University)

Abstract:
When is nothing really something? When it leads to a revelation about boron, an element with worlds of unexplored potential.

Flat boron may take many forms: Rice University researchers find two-dimensional boron has potential advantages over graphene

Houston, TX | Posted on April 23rd, 2012

Theoretical physicist Boris Yakobson and his team at Rice University have taken an unusual approach to analyzing the possible configurations of two-dimensional sheets of boron, as reported this week in the American Chemical Society journal Nano Letters.

Treating it as Swiss cheese - in which the holes are as defining as the cheese itself - was the key concept in figuring out what atom-thin sheets of boron might look like. Those sheets, when rolled into a hollow tube, or nanotube, could have a distinct advantage over carbon nanotubes; boron nanotubes are always metallic, while the carbon atoms in a nanotubes can bearranged to form either metallic or semiconducting nanotubes. This variation in atomic arrangement -- known as chirality -- is one of the major hurdles to carbon nanotube processing and development.

"If I dream wildly, I like to think boron nanotubes would make a great energy-transporting quantum wire," said Yakobson, Rice's Karl F. Hasselmann Professor of Mechanical Engineering and Materials Science andprofessor of chemistry. "It would have the benefits of carbon, but without the challenge of selecting a particular symmetry."

A boron lattice, even in just two dimensions, can have a range of configurations, Yakobson said. Fully packed, it's a layer of atoms arranged in triangles. That's one extreme. But take one atom out, and what was six triangles becomes a hexagon. Take all such possible atoms out and the sheet looks exactly like graphene, the two-dimensional, single-atom thick form of carbon that has been all the rage in the world of chemistry and materials science for the past decade.

Between those two extremes are thousands of possible forms of pure boron in which missing atoms leave patterns of hexagonal holes.

"Carbon is well-defined," said Yakobson, whose theories focus on the interactions at play among atoms as they bond and break. "Any deviation in graphene's hexagonal form is what we call a defect, which has negative connotations.

"But we find there is a rich variety in two-dimensional boron," he said. "It's all purified - there's no non-boron here, even though there are vacancies, empty sites. The amazing thing is that nature prefers to have it that way; Not hexagonal, where every third position is missing an atom, and not a triangular lattice. The optimum is right in the middle."

In that most-stable middle ground, the researchers found 10 to 15 percent of the boron atoms in a lattice were missing, leaving "vacancy concentrations" in a variety of patterns.

Yakobson said using traditional computational methods to assess thousands of boron configurations would have cost too much and taken too long. So he and Rice research scientist Evgeni Penev applied cluster expansion, a method of calculation more commonly applied to alloys.

"Evgeni gave it a twist: He treated the empty spaces as the second alloy ingredient, in the same way you can't have Swiss cheese without 'alloyed in' voids and real cheese. In this calculation, the holes are an equal, physical entity."

With space as a pseudoalloy, the researchers found a range of formation energies one might employ to identify stable sheets of boron with particular vacancy concentrations. They also found that synthesized boron layers would probably be polymorphic: Each sheet could contain a jumble of patterns and still be considered pure boron.

"Polymorphic means that all these possibilities are pretty much equal, and equally likely to form," Yakobson said.

"This is a small part of the fundamental physics," Penev said. "The next step is to consider more practical things, like whether it can be synthesized and under what conditions."

Yakobson, who in 2007 first theorized the possibility of an 80-atom boron "buckyball," said that while boron is difficult to work with, that difficulty makes it more rewarding. "On one hand, it's very hard to conceive a possibility or to get experimental evidence. On the other hand, the field isn't as crowded as graphene."

Co-authors of the paper are Rice postdoctoral researchers Somnath Bhowmick and Arta Sadrzadeh.

The research was supported by the Department of Energy and the National Science Foundation through funding of Rice's DAVinCI computer cluster, administered by the Ken Kennedy Institute for Information Technology.

####

About Rice University
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 known for its "unconventional wisdom." 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. 4 for "best value" among private universities by Kiplinger's Personal Finance. To read "What they're saying about Rice," go to www.rice.edu/nationalmedia/Rice.pdf.

For more information, please click here

Contacts:
David Ruth
713-348-6327


Mike Williams
713-348-6728

Copyright © Rice University

If 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.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Read the abstract at:

Related News Press

News and information

The speed limit for intra-chip communications in microprocessors of the future January 23rd, 2017

New, old science combine to make faster medical test: Nanoparticles and Faraday rotation allow faster diagnoses January 23rd, 2017

Traffic jam in empty space: New success for Konstanz physicists in studying the quantum vacuum January 22nd, 2017

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

Ultra-precise chip-scale sensor detects unprecedentedly small changes at the nanoscale January 20th, 2017

Physics

Traffic jam in empty space: New success for Konstanz physicists in studying the quantum vacuum January 22nd, 2017

NIST physicists 'squeeze' light to cool microscopic drum below quantum limit January 12th, 2017

First experimental proof of a 70 year old physics theory: First observation of magnetic phase transition in 2-D materials, as predicted by the Nobel winner Onsager in 1943 January 6th, 2017

Diamonds are technologists' best friends: Researchers from the Lomonosov Moscow State University have grown needle- and thread-like diamonds and studied their useful properties December 30th, 2016

Chemistry

Chemistry on the edge: Experiments at Berkeley Lab confirm that structural defects at the periphery are key in catalyst function January 13th, 2017

Graphene/ Graphite

Researchers design one of the strongest, lightest materials known: Porous, 3-D forms of graphene developed at MIT can be 10 times as strong as steel but much lighter January 7th, 2017

Nano-chimneys can cool circuits: Rice University scientists calculate tweaks to graphene would form phonon-friendly cones January 4th, 2017

Govt.-Legislation/Regulation/Funding/Policy

The speed limit for intra-chip communications in microprocessors of the future January 23rd, 2017

Traffic jam in empty space: New success for Konstanz physicists in studying the quantum vacuum January 22nd, 2017

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

'5-D protein fingerprinting' could give insights into Alzheimer's, Parkinson's January 19th, 2017

Chip Technology

The speed limit for intra-chip communications in microprocessors of the future January 23rd, 2017

Explaining how 2-D materials break at the atomic level January 20th, 2017

New research helps to meet the challenges of nanotechnology: Research helps to make the most of nanoscale catalytic effects for nanotechnology January 20th, 2017

Ultra-precise chip-scale sensor detects unprecedentedly small changes at the nanoscale January 20th, 2017

Nanotubes/Buckyballs/Fullerenes

Captured on video: DNA nanotubes build a bridge between 2 molecular posts: Research may lead to new lines of direct communication with cells January 9th, 2017

Nano-chimneys can cool circuits: Rice University scientists calculate tweaks to graphene would form phonon-friendly cones January 4th, 2017

WPI researchers build liquid biopsy chip that detects metastatic cancer cells in blood December 15th, 2016

Infrared instrumentation leader secures exclusive use of Vantablack coating December 5th, 2016

Discoveries

The speed limit for intra-chip communications in microprocessors of the future January 23rd, 2017

New, old science combine to make faster medical test: Nanoparticles and Faraday rotation allow faster diagnoses January 23rd, 2017

Traffic jam in empty space: New success for Konstanz physicists in studying the quantum vacuum January 22nd, 2017

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

Materials/Metamaterials

A toolkit for transformable materials: How to design materials with reprogrammable shape and function January 20th, 2017

Explaining how 2-D materials break at the atomic level January 20th, 2017

Chemists Cook up New Nanomaterial and Imaging Method: Nanomaterials can store all kinds of things, including energy, drugs and other cargo January 19th, 2017

Strength of hair inspires new materials for body armor January 18th, 2017

Announcements

The speed limit for intra-chip communications in microprocessors of the future January 23rd, 2017

New, old science combine to make faster medical test: Nanoparticles and Faraday rotation allow faster diagnoses January 23rd, 2017

Traffic jam in empty space: New success for Konstanz physicists in studying the quantum vacuum January 22nd, 2017

A big nano boost for solar cells: Kyoto University and Osaka Gas effort doubles current efficiencies January 21st, 2017

Quantum nanoscience

The speed limit for intra-chip communications in microprocessors of the future January 23rd, 2017

First experimental proof of a 70 year old physics theory: First observation of magnetic phase transition in 2-D materials, as predicted by the Nobel winner Onsager in 1943 January 6th, 2017

Quantum simulation technique yields topological soliton state in SSH model January 3rd, 2017

Diamonds are technologists' best friends: Researchers from the Lomonosov Moscow State University have grown needle- and thread-like diamonds and studied their useful properties December 30th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project