New X-ray Scope Reveals 3-D Nanostructures

A new full field transmission x-ray microscope (TXM) now makes it possible to rapidly capture and integrate thousands of two-dimensional images to create digital three-dimensional constructs with high accuracy. The direct observation of structures spanning 25 nm will offer fundamental advances in the fields of energy research, biology, national defense and environmental sciences.

The TXM was developed and commissioned at Brookhaven National Laboratory’s National Synchrotron Light Source (NSLS), which has the x-ray source needed to capture images on the nanoscale. The new system rapidly combines 2-D images taken from every angle to form digital 3-D constructs.

Collaborators from Photon Sciences and Sustainable Energy Technologies stand behind the new transmission x-ray microscope (TXM) at Brookhaven’s National Synchrotron Light Source. From left: Yu-chen Karen Chen-Wiegart, Can Erdonmez, Jun Wang and Christopher Eng. (Images: Brookhaven National Lab)

“We can actually see the internal 3-D structure of materials at the nanoscale,” said Jun Wang, a Brookhaven physicist. “The device works beautifully, and it overcomes several major obstacles for x-ray microscopes.”

Wang’s group used the TXM to examine a 20-µm electrode of a lithium-ion battery. The sample was placed on a platform equipped with three sensors, which measured nanoscale shifts in all directions while the battery rotated and the microscope captured 1441 2-D images. The images were calibrated using a gold sphere and then recorded by the computer, which precisely assembled the images to form the final 3-D construct after automatically compensating for any shifts. The entire process took only four hours, with the speed attributable more to the x-ray source than to the microscope or computer.

In addition to direct structural observation, the TXM will also offer chemical and elemental understanding of materials, allowing scientists to identify individual chemical configurations within samples. Wang’s team is currently working on demonstrating this capability.

This 3-D reconstruction of a lithium-ion battery electrode, composed of 1441 individual images captured and aligned by the TXM, reveals nanoscale structural details to help guide future energy research.

The x-ray microscope will focus mainly on storage solutions and alternative energy fuels, but fundamental insights already have been applied to plant root structures, catalysts and advanced electronics.

The TXM’s capabilities can be exploited further when Brookhaven’s NSLS-II comes online in 2015. The NSLS-II’s higher beam flux, or x-ray brightness, will allow it to image 1000 times faster than the current light source.

Built by Xradia, a California-based company specializing in 3-D x-ray microscopy, TXM was funded by the American Reinvestment and Recovery Act. Brookhaven operates under the auspices of the US Department of Energy.

The results of the experiments performed on the TXM were reported in Applied Physics Letters.

For more information, visit: www.bnl.gov