Carbon nanotubes + photoluminescent supramolecules -> new catalysts

July 13, 2011
Supra Molecule

Binding carbon nanotubes to a porous silicate particles allows for testing CNT-photoluminescent molecule interactions (credit: Rice University)

Chemists at Rice University have created a platform to analyze interactions between carbon nanotubes and a wide range of photoluminescent materials.

The microscopic particles combine single-walled carbon nanotubes with porous silicate materials that can absorb various molecules such as a photoactive ruthenium complex. The research involved dissolving the bundles in chlorosulfonic acid, which added protons (a positive charge) to each nanotube. This made the nanotubes attractive to three types of silicate particles tested.

“Basically, we found out that if you put a photoactive species (ruthenium) there and excite it with light, two different processes happen. If it has carbon nanotubes close by, it will transfer an electron to the nanotubes. There’s a charge transfer, and we knew that would happen,” said Angel Martí, an assistant professor of chemistry and bioengineering. “What we didn’t expect when we analyzed the spectrum was seeing two different species of ruthenium complexes, one with a very short photoluminescence lifetime and one very long.”

The platform could be key to unlocking better methods for catalysis, artificial photosynthesis or splitting water into hydrogen, the researchers said.

Ref.: Angel A. Martí, et al., Single-walled carbon nanotubes shell decorating porous silicate materials: A general platform for studying the interaction of carbon nanotubes with photoactive molecules, Chemical Science, 2011; [DOI: 10.1039/C1SC00323B]