Single Bonds Between Atoms Imaged
One of the most important parts of any scientific discovery is observation, as that is how you determine if your hypotheses are to be rejected. As researchers work to find ways to using graphene for electronic components, they have to observe the processes used to manipulate the carbon allotrope to ensure it is doing what they want it to do. This is what researchers at Berkeley Lab were working on when they directly imaged the atomic bonds with the carbon molecules they were working with.
Graphene is a single-atom thick sheet of carbon with extraordinary properties that will make it very useful in electronics. The catch is that manufacturing it in the necessary forms is difficult, so researchers are trying to isolate the best processes to use. To simplify the search, the Berkeley Lab researchers decided to place the molecules on a silver substrate, instead of in a solution, and ran a non-contact Atomic Force Microscope (nc-AFM) over it. All AFMs work by running a highly sensitive needle over a target to feel it, but a nc-AFM does not touch the target; instead it senses the energy changes due to chemical bonds. Once the data was processed into images, the researchers were able to actually see the individual chemical bonds, like they were diagrams in a textbook.
While it is amazing and impressive that the researchers were able to take these images, they did show that the researchers' initial expectations were wrong, concerning the reactions of the molecules they were working with. Fortunately this research will go a long way in understanding the processes involved in growing graphene structures.
Source: Berkeley Lab