Organic molecular interactions unveiled

 

For the first time, researchers have directly seen how organic molecules bind to other materials at the atomic level.

 

Using high resolution TEM, researchers have studied organic molecular interactions on carbon nanotubes, providing information that could, for example, increase the life span of organic electronic devices. 

 

Recent progress using HR-TEM has enabled researchers to observe the structures, movements and reactions of single, small organic molecules.

 

However, visualising precise molecular amorphous structures at the atomic level has remained a challenge. 

 

With this in mind researchers from Kyoto University's Institute for Integrated Cell-Material Sciences (iCeMS) and Japan's National Institute of Advanced Industrial Science and Technology together with colleagues from Finland's Tampere University of Technology developed a method to investigate molecular interactions on single-walled carbon nanotubes.

 

They first linked pyrene, a hydrocarbon composed of four flat benzene rings, to a single-walled carbon nanotube, and then used HR-TEM to see the link.

 

The researchers used a JEOL JEM-2100F microscope equipped with Delta spherical aberration correctors at an electron acceleration voltage of 60 kV, as well as a JEOL JEM-2010F microscope equipped with a CEOS Cs corrector at 120 kV.

 

HR-TEM images were recorded using CCD cameras installed in these microscopes at a rate of 1 frame s−1, with TEM image simulation then performed using SimulaTEM software.

 

Crucially, the structure of the pyrene was clearly imaged, with the researchers providing the first images of individual planar polycyclic aromatic compounds linked covalently to the exterior surface of nanocarbon scaffolds.

 

 

"This same methodology can be used to study any organic molecules that contain an aryl group," says Tomokazu Umeyama from iCeMS. "The methodology has the potential to provide indispensable information regarding molecular interactions."

 

Research is published in Nature Communications