a boon for nanotechnologyBy Tona Kunz, Argonne National Laboratory, April 9, 2013
The study of nanoscale material just got much easier, and the design of nanoscale technology could get much more efficient, thanks to an advance in X-ray analysis.
Nanomaterials develop new physical and chemical properties, such as superconductivity and enhanced strength, when exposed to extreme pressure. A better understanding of how and when those changes occur can guide the design of better products that use nanotechnology.
But high-energy X-rays produced by lightsources such as the Advanced Photon Source (APS) at Argonne National Laboratory are the only way to study the in-situ structural changes induced by pressure in nanomaterials, and those studies have lacked precision.
As reported in a Carnegie Institute of Science press release, an international team of scientists using the APS detailed in the April 9 issue of the journal Nature Communications that they devised a way to overcome the distortion caused by sample environments used with the X-rays to improve spatial resolution imaging by two orders of magnitude. This 30-nanometer resolution greatly reduces uncertainties for studies of nanoscale materials. Researchers expect to fine-tune the technique to reach resolutions of a few nanometers in subsequent experiments.
"Before, we had to average the strain on polycrystals (solids composed of many microscopic crystals) or over an entire single crystal under high pressure," said Wenge Yang of the Carnegie Institution of
Washington and the High Pressure Synergetic Consortium at the APS. "But now we can zoom in like a microscope on a single crystal and even inside a single crystal. We will continue to improve this. There are still two orders of magnitudes in length scale we can achieve before reaching the diffraction limit of hard x-rays."
The team of researchers led by Wenge used the APS beamline 34-ID-C to demonstrate a proof of principle of the new imaging technique by looking at gold nanocrystal as reported in the paper "Coherent diffraction imaging of nanoscale evolution in a single crystal under high pressure".
The imaging technique uses an algorithm developed at the London Centre for Nanotechnology and X-ray instrumentation pioneered at the APS.mThe technique opens the door to a variety of new research and can be used at third- and fourth-generation lightsources, which produce highly coherent X-rays.
Improved spatial resolution imaging for nanomaterial under high pressure has ramifications for advanced engineering, such as the development of nanoscale coatings for semiconductors that can better withstand
high currents and heat loads.
An accurate structural view of nanoscale materials under pressure can aid in redesigning materials at larger scales to exhibit the same high-performance traits.
Improved imaging also can aid studies of minerals under high-pressure to mimic the real conditions from earth’s crust to mantle, even core conditions.