Credit: Azubel-fig

The need for improved imaging and characterization on the nanoscale was emphasized in the 2007 Roadmap and again at the 2013 Foresight Conference on Atomic Precision. We noted last year a new advancement in atomic-scale resolution of 10-nm platinum particles, requiring multiple imaging techniques in combination, and recently the marked improvement in optical imaging for characterization of biological machinery at 1-nm. Now researchers at Stanford University successfully used high-resolution electron microscopy alone to characterize 1-nm gold nanoparticles (containing 68 gold atoms) – a capability new enough that x-ray scattering was used to verify the result.  This type of advancement could help remove one of the bottlenecks in progress towards nanometer-scale manufacturing.

The news release, from the Academy of Finland (the structure of the nanoparticle had been predicted by researchers at University of Jyväskylä, Finland), was reprinted at Phys.org:

Electron microscopy is similar in principle to conventional light microscopy, with the exception that the wavelength of the electron beam used for imaging is close to the spacing of atoms in solid matter, about a tenth of a nanometre, in contrast with the wavelength of visible light, which is hundreds of nanometres. A crucial aspect of the new work is the irradiation of the nanoparticle with very few electrons to avoid perturbing the structure of the nanoparticle. The success of this approach opens the way to the determination of many more nanoparticle structures and to both fundamental understanding and practical applications.

With the progress recently described in assembly-line style molecular synthesis and new NSF and DARPA funding for nanomanufacturing (see several recent posts), increased emphasis on imaging and characterization across each incremental size regime should receive more targeted attention.
-Posted by Stephanie C, Oct 2014