Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Simultaneous Nanoscale Imaging of Surface and Bulk Atoms

Uranium single atoms (circled) and small crystallites on a carbon support imaged simultaneously using a scanning probe to produce forward scattering through the sample (top) and backward scattering emerging from the surface (bottom). Center panel shows superimposition of the two in red (bulk) and green (surface). Atoms not seen in the lower image are on the bottom surface of the support.
Uranium single atoms (circled) and small crystallites on a carbon support imaged simultaneously using a scanning probe to produce forward scattering through the sample (top) and backward scattering emerging from the surface (bottom). Center panel shows superimposition of the two in red (bulk) and green (surface). Atoms not seen in the lower image are on the bottom surface of the support.

Abstract:
New microscope could revolutionize imaging, improve catalysts for energy applications

Simultaneous Nanoscale Imaging of Surface and Bulk Atoms

Upton, NY | Posted on September 21st, 2009

Scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory, in collaboration with researchers from Hitachi High Technologies Corp., have demonstrated a new scanning electron microscope capable of selectively imaging single atoms on the top surface of a specimen while a second, simultaneous imaging signal shows atoms throughout the sample's depth. This new tool, located at Brookhaven Lab's Center for Functional Nanomaterials (CFN), will greatly expand scientists' ability to understand and ultimately control chemical reactions, such as those of catalysts in energy-conversion devices.

A paper describing the work will be published online September 20, 2009, in Nature Materials, along with a commentary article highlighting the development.

"Our knowledge of the role of individual atoms in nanotechnology and energy-related research is strongly influenced by our ability to visualize them, not only in bulk but also on the surface, which is where the interactions of chemical reactions take place," said Brookhaven physicist Yimei Zhu, lead author on the paper. "This new microscope and the method we developed allow us, for the first time, to directly look at atoms on the top surface and in the bulk of a sample simultaneously to reveal their atomic arrangement and bonding states. This information will help us identify the active sites and functions of materials at nanoscale dimensions for a wide range of applications, such as converting waste heat or chemical energy to electricity."

Like all scanning electron microscopes, the new tool probes a sample with an electron beam focused to a tiny spot and detects so-called secondary electrons emitted by the sample to reveal its surface structure and topography. Though this technique has been a workhorse of surface imaging in industrial and academic laboratories for decades, its resolution has left much to be desired because of imperfect focusing due to lens aberrations.

Using a newly developed spherical aberration corrector, the new tool corrects these distortions to create a smaller probe with significantly increased brightness.

"The effect is similar to using a larger aperture lens on a camera," said biophysicst Joseph Wall, a longtime expert in electron microscopy at Brookhaven Lab and a co-author on the paper. "It allows you to gather information from a larger angle and focus on a smaller spot."

The new device also employs specialized electron optics to channel the emitted secondary electrons to the detector. The result is a fourfold improvement in resolution to below one tenth of a nanometer — and thus, the ability to image single atoms.

Additional detectors, located below the sample, detect electrons transmitted through the sample, revealing details about the entire structure at the exact instant the "shutter" snapped to record each pixel of the surface image. This simultaneous imaging allows the scientists to correlate information in the two images to understand precisely what is happening on the surface and throughout the sample at the same time.

"Having information about the surface structure and the bulk sample at the same time will allow researchers to better determine how the surface and bulk atoms work together, for example in a catalytic reaction," said Zhu. The improved resolution and combined imaging capabilities will also reveal features such as small variations in composition or the locations of impurities that could have large effects on function.

"An essential component of this study was selection of a test specimen, isolated uranium atoms on a thin carbon substrate, where the images could be interpreted quantitatively to rule out other possible interpretations," Wall commented.

Because of its extreme sensitivity, the new microscope must be kept isolated from a range of environmental effects such as variations in temperature, mechanical vibrations, and electromagnetic fields. Even the slightest waft of air could cause distortions in the images.

Fortunately the CFN was built with these needs in mind. Temperatures are regulated to within three-hundredths of a degree Fahrenheit over a 24-hour period; shock-absorber-like slabs isolate the room from the rumble of passing trucks and distant slamming doors; layers of heavy doors keep even subtle vibrations out; and air-cooling panels replace typical ceiling vents to eliminate airflow.

"The building is really a mechanical-engineering masterpiece," said Zhu. "This microscope wouldn't work at all without these sophisticated systems." Development of the microscope was funded by the Office of Basic Energy Sciences within the DOE Office of Science.

The Center for Functional Nanomaterials at Brookhaven National Laboratory is one of the five DOE Nanoscale Science Research Centers (NSRCs), premier national user facilities for interdisciplinary research at the nanoscale. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE's Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge and Sandia and Los Alamos national laboratories. For more information about the DOE NSRCs, please visit DOE's nanoscience website at www.science.doe.gov/news_information/news_room/2006/nano/index.htm

####

About Brookhaven National Laboratory
One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry and government researchers. Brookhaven is operated and managed for DOE's Office of Science by Brookhaven Science Associates, a limited-liability company founded by Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization.

For more information, please click here

Contacts:
Karen McNulty Walsh
(631) 344-8350

Mona S. Rowe
(631) 344-5056

Copyright © Brookhaven National Laboratory

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 News Press

News and information

Iranian Scientists Use Artemisia Annua Plant to Produce Breast Cancer Drugs August 29th, 2015

Small but heading for the big time: Nanobiotix half year results for the six months ended 30 June 2015, in line with expectations: Major clinical achievements and corporate developments August 28th, 2015

A new technique to make drugs more soluble August 28th, 2015

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Chemistry

A new technique to make drugs more soluble August 28th, 2015

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Announcements

Iranian Scientists Use Artemisia Annua Plant to Produce Breast Cancer Drugs August 29th, 2015

Small but heading for the big time: Nanobiotix half year results for the six months ended 30 June 2015, in line with expectations: Major clinical achievements and corporate developments August 28th, 2015

A new technique to make drugs more soluble August 28th, 2015

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Tools

Nanolab Technologies LEAPS Forward with High-Performance Analysis Services to the World: Nanolab Orders Advanced Local Electrode Atom Probe (LEAP®) Microscope from CAMECA Unit of AMETEK Materials Analysis Division August 27th, 2015

Nanometrics to Participate in the Citi 2015 Global Technology Conference August 26th, 2015

50 Years of Scanning Electron Microscopy from ZEISS: ZEISS celebrates the birth of the first commercial scanning electron microscope in 1965 August 26th, 2015

Announcing Oxford Instruments and School of Physics signing a Memorandum of Understanding August 26th, 2015

Energy

Nanocatalysts improve processes for the petrochemical industry August 28th, 2015

Nanotechnology that will impact the Security & Defense sectors to be discussed at NanoSD2015 conference August 25th, 2015

Industrial Nanotech, Inc. Provides Update On Hospital Project, PCAOB Audit, and New Heat Shield™ Line August 24th, 2015

Novel nanostructures for efficient long-range energy transport August 21st, 2015

Alliances/Trade associations/Partnerships/Distributorships

National Space Society Welcomes Janet Ivey As New NSS Governor: Janet Ivey of Janet's Planet is NOW IN ORBIT as a member of the Board of Governors of the National Space Society August 27th, 2015

National Space Society Welcomes Geoff Notkin As New NSS Governor August 26th, 2015

XEI Scientific appoints EM Resolutions as Distributor for the UK & Irish markets August 11th, 2015

Omni Nano and Time Warner Cable Partner to Provide Nanotechnology Education to the Boys & Girls Clubs of Los Angeles: A $10,000 Donation to Benefit Youth of Los Angeles County's Boys & Girls Clubs August 4th, 2015

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







Car Brands
Buy website traffic