By now we’ve all seen AFM images of individual atoms — in black and white. Why only B&W? Why can’t the AFM show us the atoms in color, having each color indicate a different chemical element, as in our molecular modeling images?
Now it can, and at room temperature, not only super-low temps as before. David Shiga at NewScientist.com brings news of an achievement in Japan:
The chemical identity of individual atoms on a surface can now be determined using an incredibly powerful atomic force microscope.
It means that scientists can now look at a mixed material and pick out individual atoms of different elements on its surface, such as tin or silicon. The advance will allow researchers to understand the structural make-up of complex materials and help them design new ones with unusual properties.
Atomic force microscopes are routinely used to spot individual atoms on surfaces and reveal how they are arranged. But previously, they have not been capable of distinguishing between atoms of different chemical elements.
Now, Yoshiaki Sugimoto at Osaka University in Japan, and colleagues, have found a way to use the atomic force microscope to produce images that reveal the chemical identity of individual atoms on a surface…
Alexander Shluger at University College London in the UK, who is not a member of Sugimoto’s team, says the ability to distinguish atoms of different elements on a surface could be useful for nanotechnology researchers trying to design devices at the molecular level.
“If you want to use this as a tool for manufacturing and a tool for nanotechnology, operating at room temperature is much more convenient, because you don’t need all this cryogenic equipment,” he told New Scientist.
Scanning tunnelling microscopes are able to make such distinctions, but they only work with conductor and semiconductor materials, a limitation not shared by atomic force microscopes, he says. “This achievement provides a more universal tool for this kind of chemical identification,” he told New Scientist.
The story is accompanied by a nice color image, showing the different atom types. A reminder for the lay reader: atoms do not really have a color; it’s a symbol, as on a roadmap.
If you can’t get into the NewScientist.com article, which is erratic, try this link for the image only. (Credit: KurzweilAI.tech) —Christine