Rice University chemists have developed a platform to study the interactions between various photoluminescent materials and carbon nanotubes.
An assistant professor of chemistry and bioengineering, Angel Martí, accumulated microscopic particles by combining porous silicate materials such as ruthenium complex with single-walled carbon nanotubes. The results of the study were reported in the Royal Society of Chemistry journal Chemical Science.
Lead author of the study, Avishek Saha, developed the new particles on a trial and error basis. They had to find a technique to prevent single-walled carbon nanotubes, manufactured using the Rice-born HiPco process, from gathering into bundles while enabling them to stick to the new particles. To solve this issue, Matteo Pasquali, a Rice professor in chemical and biomolecular engineering and in chemistry, suggested mixing the bundles in chlorosulfonic acid, which involved the addition of protons to induce a positive charge to individual nanotubes.
Using this method, the nanotubes were made to attract various kinds of tested silicate particles including a commercial type of MCM-41, which is a mesoporous material that serves as a molecular sieve, another type of MCM-41 manufactured at Rice, and microporous Zeolyte-Y.
The introduction of ruthenium molecules marked a significant step in the experiment. The ruthenium molecules were absorbed by silicates, thus brining them close to an array of nanotubes. The ruthenium complexes would undergo photoluminesce under a spectroscope. The researchers observed that ruthenium complexes in the middle of the sponge were retained at a far distance from the nanotubes and so it maintained its standard luminescence.
Saha explained that the research shows promising potential in the field of material science. She added that by combining MCM and carbon nanotubes, a hybrid material can be developed that offers the benefits of both. Pores in zeolites cannot be penetrated owing to their crystalline arrangement at 0.7 nm. However, pores in MCM can be modified to absorb certain materials.
Source: http://media.rice.edu/