Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > In borophene, boundaries are no barrier: Rice U., Northwestern researchers make and test atom-thick boron's unique domains

A scanning electron microscope image (top) shows two periodic assemblies of borophene, a synthetic, two-dimensional array of boron atoms, that join at a line defect. Computational models in the middle and bottom images correspond to the regions, with 1-to-6 borophene in red and 1-to-5 in blue. Researchers at Rice and Northwestern universities determined that phases of borophene line up in such a way that the material's conductive, metallic nature is maintained. (Credit: Graphics by Luqing Wang/Rice University)
A scanning electron microscope image (top) shows two periodic assemblies of borophene, a synthetic, two-dimensional array of boron atoms, that join at a line defect. Computational models in the middle and bottom images correspond to the regions, with 1-to-6 borophene in red and 1-to-5 in blue. Researchers at Rice and Northwestern universities determined that phases of borophene line up in such a way that the material's conductive, metallic nature is maintained. (Credit: Graphics by Luqing Wang/Rice University)

Abstract:
Borophene, the atomically flat form of boron with unique properties, is even more interesting when different forms of the material mix and mingle, according to scientists at Rice and Northwestern universities.

In borophene, boundaries are no barrier: Rice U., Northwestern researchers make and test atom-thick boron's unique domains

Houston, TX | Posted on July 17th, 2018

Scientists at the institutions made and analyzed borophene with different lattice arrangements and discovered how amenable the varied structures are to combining into new crystal-like forms. These, they indicated, have properties electronics manufacturers may wish to explore.

The research led by Rice materials theorist Boris Yakobson and Northwestern materials scientist Mark Hersam appears in Nature Materials.

Borophene differs from graphene and other 2D materials in an important way: It doesn't appear in nature. When graphene was discovered, it was famously yanked from a piece of graphite with Scotch tape. But semiconducting bulk boron doesn't have layers, so all borophene is synthetic.

Also unlike graphene, in which atoms connect to form chicken wire-like hexagons, borophene forms as linked triangles. Periodically, atoms go missing from the grid and leave hexagonal vacancies. The labs investigated forms of borophene with "hollow hexagon" concentrations of one per every five triangles and one per every six in the lattice.

These are the most common phases the Northwestern lab observed when it created borophene on a silver substrate through atomic boron deposition in an ultrahigh vacuum, according to the researchers, but "perfect" borophene arrays weren't the target of the study.

The lab found that at temperatures between 440 and 470 degrees Celsius (824-878 degrees Fahrenheit), both 1-to-5 and 1-to-6 phases grew simultaneously on the silver substrate, which acts as a template that guides the deposition of atoms into aligned phases. The labs' interest was heightened by what happened where these domains met. Unlike what they had observed in graphene, the atoms easily accommodated each other at the boundaries and adopted the structures of their neighbors.

These boundary adjustments gave rise to more exotic – but still metallic – forms of borophene, with ratios such as 4-to-21 and 7-to-36 appearing among the parallel phases.

"In graphene, these boundaries would be disordered structures, but in borophene the line defects, in effect, are a perfect structure for each other," said Rice graduate student Luqing Wang, who led a theoretical analysis of atom-level energies to explain the observations. "The intermixing between the phases is very different from what we see in other 2D materials."

"While we did expect some intermixing between the 1-to-5 and 1-to-6 phases, the seamless alignment and ordering into periodic structures was surprising," Hersam said. "In the two-dimensional limit, boron has proven to be an exceptionally rich and interesting materials system."

Wang's density functional theory calculations revealed the metallic nature of the line defects; this implied that unlike insulating defects in otherwise metallic graphene, they have minimal impact on the material's electronic properties at room temperature. At low temperature, the material shows evidence of a charge density wave, a highly ordered flow of electrons.

Theoretical calculations also suggested subtle differences in stiffness, thermal conductivity and electrochemical properties among borophene phases, which also suggested the material can be tuned for applications.

"The unique polymorphisms of borophene are on full display in this study," Yakobson said. "This suggests intriguing interplay in the material's electronic structure through charge density waves, which may lead to tantalizing switchable electronics."

"As an atomically thin material, borophene has properties that should be a function of the substrate, neighboring materials and surface chemistry," Hersam said. "We hope to gain further control over its properties through chemical functionalization and/or integration with other materials into heterostructures."

Yakobson and Hersam also co-authored a recent Nature Nanotechnology perspective about "the lightest 2D metal." In that piece, the authors suggested borophene may be ideal for flexible and transparent electronic interconnects, electrodes and displays. It could also be suitable for superconducting quantum interference devices and, when stacked, for hydrogen storage and battery applications.

Co-authors of the Nature Materials paper are graduate student Xiaolong Liu of Northwestern and Rice alumnus Zhuhua Zhang, now a professor at the Nanjing University of Aeronautics and Astronautics. Hersam is the Walter P. Murphy Professor of Materials Science and Engineering at Northwestern. Yakobson is the Karl F. Hasselmann Professor of Materials Science and NanoEngineering and a professor of chemistry at Rice.

Zhang co-authored the Nature Nanotechnology paper with Northwestern and Argonne National Laboratory alumnus Andrew Mannix, now a postdoctoral fellow at the University of Chicago, and Argonne materials scientist Nathan Guisinger.

The research was supported by the Office of Naval Research, the National Science Foundation Materials Research Science and Engineering Center, the Army Research Office, the Robert Welch Foundation, the Department of Energy Office of Science, the State Key Laboratory of Mechanics and Control of Mechanical Structures at Nanjing University of Aeronautics and Astronautics and the Northwestern University International Institute for Nanotechnology.

####

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 home to the Baker Institute for Public Policy. With 3,970 undergraduates and 2,934 graduate students, Rice’s undergraduate student-to-faculty ratio is just under 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for quality of life and for lots of race/class interaction and No. 2 for happiest students by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger’s Personal Finance. To read “What they’re saying about Rice,” go to http://tinyurl.com/RiceUniversityoverview .

Follow Rice News and Media Relations via Twitter @RiceUNews.

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:

Borophene as a prototype for synthetic 2D materials development:

Long may you wave, borophene:

Boron atoms stretch out, gain new powers:

Borophene shines alone as 2D plasmonic material:

Yakobson Research Group:

Hersam Research Group:

Rice Department of Materials Science and NanoEngineering:

Related News Press

News and information

CTI Materials drives nano commercialization with it's patented surfactant free nanoparticle dispersions August 15th, 2018

Flipping the switch on supramolecular electronics August 14th, 2018

New technology can detect hundreds of proteins in a single sample: Improvement of barcoding technique offers cost-effective alternative to current technology August 13th, 2018

Amazingly 'green' synthesis method for high-tech dyes: Dyes that are also of great interest for organic electronics have recently been prepared and crystallised at TU Wien. All that is required is just water, albeit under highly unusual conditions. August 10th, 2018

Yale-NUS scientist and collaborators solve open theoretical problem on electron interactions August 10th, 2018

Graphene/ Graphite

CTI Materials drives nano commercialization with it's patented surfactant free nanoparticle dispersions August 15th, 2018

Flipping the switch on supramolecular electronics August 14th, 2018

2 Dimensional Materials

Flipping the switch on supramolecular electronics August 14th, 2018

Govt.-Legislation/Regulation/Funding/Policy

Flipping the switch on supramolecular electronics August 14th, 2018

New technology can detect hundreds of proteins in a single sample: Improvement of barcoding technique offers cost-effective alternative to current technology August 13th, 2018

Breaking down the Wiedemann-Franz law: In a study exploring the coupling between heat and particle currents in a gas of strongly interacting atoms, physicists at ETH Zurich find puzzling behaviours August 10th, 2018

Yale-NUS scientist and collaborators solve open theoretical problem on electron interactions August 10th, 2018

Possible Futures

How hot is Schrödinger's coffee? August 15th, 2018

New technology can detect hundreds of proteins in a single sample: Improvement of barcoding technique offers cost-effective alternative to current technology August 13th, 2018

Biomimetic micro/nanoscale fiber reinforced composites August 10th, 2018

Breaking down the Wiedemann-Franz law: In a study exploring the coupling between heat and particle currents in a gas of strongly interacting atoms, physicists at ETH Zurich find puzzling behaviours August 10th, 2018

Discoveries

How hot is Schrödinger's coffee? August 15th, 2018

Flipping the switch on supramolecular electronics August 14th, 2018

New technology can detect hundreds of proteins in a single sample: Improvement of barcoding technique offers cost-effective alternative to current technology August 13th, 2018

Breaking down the Wiedemann-Franz law: In a study exploring the coupling between heat and particle currents in a gas of strongly interacting atoms, physicists at ETH Zurich find puzzling behaviours August 10th, 2018

Materials/Metamaterials

CTI Materials drives nano commercialization with it's patented surfactant free nanoparticle dispersions August 15th, 2018

Flipping the switch on supramolecular electronics August 14th, 2018

Biomimetic micro/nanoscale fiber reinforced composites August 10th, 2018

Yale-NUS scientist and collaborators solve open theoretical problem on electron interactions August 10th, 2018

Announcements

How hot is Schrödinger's coffee? August 15th, 2018

CTI Materials drives nano commercialization with it's patented surfactant free nanoparticle dispersions August 15th, 2018

Flipping the switch on supramolecular electronics August 14th, 2018

New technology can detect hundreds of proteins in a single sample: Improvement of barcoding technique offers cost-effective alternative to current technology August 13th, 2018

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

How hot is Schrödinger's coffee? August 15th, 2018

New technology can detect hundreds of proteins in a single sample: Improvement of barcoding technique offers cost-effective alternative to current technology August 13th, 2018

Biomimetic micro/nanoscale fiber reinforced composites August 10th, 2018

Breaking down the Wiedemann-Franz law: In a study exploring the coupling between heat and particle currents in a gas of strongly interacting atoms, physicists at ETH Zurich find puzzling behaviours August 10th, 2018

Military

Biomimetic micro/nanoscale fiber reinforced composites August 10th, 2018

UMBC researchers develop nanoparticles to reduce internal bleeding caused by blast trauma July 13th, 2018

Carbon is the new black: Researchers use carbon nanotubes to develop clothing that can double as batteries July 10th, 2018

High-power electronics keep their cool with new heat-conducting crystals July 6th, 2018

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Breaking down the Wiedemann-Franz law: In a study exploring the coupling between heat and particle currents in a gas of strongly interacting atoms, physicists at ETH Zurich find puzzling behaviours August 10th, 2018

Yale-NUS scientist and collaborators solve open theoretical problem on electron interactions August 10th, 2018

Nanotube 'rebar' makes graphene twice as tough: Rice University scientists test material that shows promise for flexible electronics August 3rd, 2018

Nanometrics Delivers 100th: Atlas III System for Advanced Process Control Metrology Atlas III: Systems are qualified and in production for advanced devices in DRAM, 3D-NAND and Foundry/Logic August 2nd, 2018

Research partnerships

Breaking down the Wiedemann-Franz law: In a study exploring the coupling between heat and particle currents in a gas of strongly interacting atoms, physicists at ETH Zurich find puzzling behaviours August 10th, 2018

Yale-NUS scientist and collaborators solve open theoretical problem on electron interactions August 10th, 2018

Scientists squeeze nanocrystals in a liquid droplet into a solid-like state and back again: Simple chemical technique transforms crystal mixture where 2 liquids meet August 9th, 2018

Quantum chains in graphene nanoribbons: Breakthrough in nanoresearch August 9th, 2018

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



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project