Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Researchers discover new phase of boron nitride and a new way to create pure c-BN

This image shows cubic boron nitride nanocrystallites.
CREDIT: Anagh Bhaumik
This image shows cubic boron nitride nanocrystallites.

CREDIT: Anagh Bhaumik

Abstract:
Researchers at North Carolina State University have discovered a new phase of the material boron nitride (Q-BN), which has potential applications for both manufacturing tools and electronic displays. The researchers have also developed a new technique for creating cubic boron nitride (c-BN) at ambient temperatures and air pressure, which has a suite of applications, including the development of advanced power grid technologies.

Researchers discover new phase of boron nitride and a new way to create pure c-BN

Raleigh, NC | Posted on February 5th, 2016

"This is a sequel to our Q-carbon discovery and converting Q-carbon into diamond," says Jay Narayan, the John C. Fan Distinguished Chair Professor of Materials Science and Engineering at NC State and lead author of a paper describing the research. "We have bypassed what were thought to be the limits of boron nitride's thermodynamics with the help of kinetics and time control to create this new phase of boron nitride.

"We have also developed a faster, less expensive way to create c-BN, making the material more viable for applications such as high-power electronics, transistors and solid state devices," Narayan says. "C-BN nanoneedles and microneedles, which can be made using our technique, also have potential for use in biomedical devices." C-BN is a form of boron nitride that has a cubic crystalline structure, analogous to diamond.

Early tests indicate that Q-BN is harder than diamond, and it holds an advantage over diamond when it comes to creating cutting tools. Diamond, like all carbon, reacts with iron and ferrous materials. Q-BN does not. The Q-BN has an amorphous structure, and it can easily be used to coat cutting tools, preventing them from reacting with ferrous materials.

"We have also created diamond/c-BN crystalline composites for next-generation high-speed machining and deep-sea drilling applications," Narayan says. "Specifically, we have grown diamond on c-BN by using pulsed laser deposition of carbon at 500 degrees Celsius without the presence of hydrogen, creating c-BN and diamond epitaxial composites."

The Q-BN also has a low work function and negative electron affinity, which effectively means that it glows in the dark when exposed to very low levels of electrical fields. These characteristics are what make it a promising material for energy-efficient display technologies.

To make Q-BN, researchers begin with a layer of thermodynamically stable hexagonal boron nitride (h-BN), which can be up to 500-1000 nanometers thick. The material is placed on a substrate and researchers then use high-power laser pulses to rapidly heat the h-BN to 2,800 degrees Kelvin, or 4,580 degrees Fahrenheit. The material is then quenched, using a substrate that quickly absorbs the heat. The whole process takes approximately one-fifth of a microsecond and is done at ambient air pressure.

By manipulating the seeding substrate beneath the material and the time it takes to cool the material, researchers can control whether the h-BN is converted to Q-BN or c-BN. These same variables can be used to determine whether the c-BN forms into microneedles, nanoneedles, nanodots, microcrystals or a film.

"Using this technique, we are able to create up to a 100- to 200-square-inch film of Q-BN or c-BN in one second," Narayan says.

By comparison, previous techniques for creating c-BN required heating hexagonal boron nitride to 3,500 degrees Kelvin (5,840 degrees Fahrenheit) and applying 95,000 atmospheres of pressure.

C-BN has similar properties to diamond, but has several advantages over diamond: c-BN has a higher bandgap, which is attractive for use in high-power devices; c-BN can be "doped" to give it positively- and negatively-charged layers, which means it could be used to make transistors; and it forms a stable oxide layer on its surface when exposed to oxygen, making it stable at high temperatures. This last characteristic means it could be used to make solid state devices and protective coatings for high-speed machining tools used in oxygen-ambient environments.

"We're optimistic that our discovery will be used to develop c-BN-based transistors and high-powered devices to replace bulky transformers and help create the next generation of the power grid," Narayan says.

####

For more information, please click here

Contacts:
Matt Shipman

919-515-6386

Copyright © North Carolina State 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

The paper, "Direct conversion of h-BN into pure c-BN at ambient temperatures and pressures in air," was published online Feb. 3 in the open-access journal APL Materials. The paper was co-authored by NC State Ph.D. student Anagh Bhaumik. The work was supported by the National Science Foundation under grant DMR-1304607:

Related News Press

News and information

Graphene key for novel hardware security May 10th, 2021

With a zap of light, system switches objects' colors and patterns: "Programmable matter" technique could enable product designers to churn out prototypes with ease May 6th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Display technology/LEDs/SS Lighting/OLEDs

Use of perovskite will be a key feature of the next generation of electronic appliances: Nanomaterials of perovskite dispersed in hexane and irradiated by laser; light emission by these materials is intense thanks to resistance to surface defects March 12th, 2021

Light-emitting tattoo engineered for the first time: Scientists at UCL and the IIT -Istituto Italiano di Tecnologia (Italian Institute of Technology) have created a temporary tattoo with light-emitting technology used in TV and smartphone screens, paving the way for a new type of March 4th, 2021

Aledia, French Developer of Next-Generation MicroLED Displays For High-Volume Consumer Markets, Announces it Has Produced its First Nanowire Chips on 300mm Silicon Wafers Using CEA-Leti Pilot Lines: Company will produce microLEDs on both 200mm and 300mm silicon wafers December 15th, 2020

An LED that can be integrated directly into computer chips: The advance could cut production costs and reduce the size of microelectronics for sensing and communication December 14th, 2020

Hardware

A Carbon Nanotube Microprocessor Mature Enough to Say Hello: Three new breakthroughs make commercial nanotube processors possible March 2nd, 2020

Powering the future: Smallest all-digital circuit opens doors to 5 nm next-gen semiconductor February 11th, 2020

SUNY Poly Professor Partners with Leading Institutions on NSF Award for Quantum Information Science Research: SUNY Poly Research Builds Upon Recent Quantum-related Research Initiatives and Workshops January 27th, 2020

Do you Kyoto? World-leading companies share their approaches to environmentally friendly business at NAUM’19 October 14th, 2019

Govt.-Legislation/Regulation/Funding/Policy

Simple robots, smart algorithms April 30th, 2021

A silver lining for extreme electronics April 30th, 2021

Less innocent than it looks: Hydrogen in hybrid perovskites: Researchers identify the defect that limits solar-cell performance April 30th, 2021

New brain-like computing device simulates human learning: Researchers conditioned device to learn by association, like Pavlov's dog April 30th, 2021

Nanomedicine

World's first fiber-optic ultrasonic imaging probe for future nanoscale disease diagnostics April 30th, 2021

Arrowhead Announces Improvement in Fibrosis after ARO-AAT Treatment in Patients with Alpha-1 Liver Disease April 28th, 2021

Silver ions hurry up, then wait as they disperse: Rice chemists show ions’ staged release from gold-silver nanoparticles could be useful property April 23rd, 2021

Synthetic gelatin-like material mimics lobster underbelly’s stretch and strength: The membrane’s structure could provide a blueprint for robust artificial tissues April 23rd, 2021

Discoveries

Graphene key for novel hardware security May 10th, 2021

With a zap of light, system switches objects' colors and patterns: "Programmable matter" technique could enable product designers to churn out prototypes with ease May 6th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Materials/Metamaterials

Silver ions hurry up, then wait as they disperse: Rice chemists show ions’ staged release from gold-silver nanoparticles could be useful property April 23rd, 2021

Synthetic gelatin-like material mimics lobster underbelly’s stretch and strength: The membrane’s structure could provide a blueprint for robust artificial tissues April 23rd, 2021

Oregon scientists create mechanism to precisely control soundwaves in metamaterials: Theoretical modeling shows that designer materials incorporating drum-like membranes allow precise stoppage and reversal of sound pulses April 16th, 2021

FSU engineers improve performance of high-temperature superconductor wires April 16th, 2021

Announcements

Graphene key for novel hardware security May 10th, 2021

With a zap of light, system switches objects' colors and patterns: "Programmable matter" technique could enable product designers to churn out prototypes with ease May 6th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

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

Graphene key for novel hardware security May 10th, 2021

With a zap of light, system switches objects' colors and patterns: "Programmable matter" technique could enable product designers to churn out prototypes with ease May 6th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Tools

World's first fiber-optic ultrasonic imaging probe for future nanoscale disease diagnostics April 30th, 2021

New Cypher VRS1250 Video-Rate Atomic Force Microscope Enables True Video-Rate Imaging at up to 45 Frames per Second April 30th, 2021

Researchers realize high-efficiency frequency conversion on integrated photonic chip April 23rd, 2021

An easy-to-use platform is a gateway to AI in microscopy April 23rd, 2021

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