Nanotubes-Porphyrine suspensions optimisation for energy transfer

Chemical functionalization of carbon nanotubes is one of the key challenges towards their use in opto-electronic devices. This technique aims at combining the great transport properties of nanotubes with the versatility of the optical properties of organic molecules. “π-stacking” functionalization of single wall carbon nanotubes with porphyrin molecules has been achieved and energy transfer has been observed from the molecules to the nanotubes by means of luminescence experiments. Nevertheless, these first trials have been performed on suspensions presenting poor stability and low photoluminescence yield. We present here a new process of functionalization that enhances the properties of these suspensions. First, the new suspensions are now stable for months ( as compared with a few days in previous works). The luminescence of these suspensions is also enhanced by more than one order of magnitude in comparison with reference. The good stability and the high luminescence yield will allow more detailed study of the electronic processes occuring in these complexes. Secondly, the nanotubes luminescence is preserved when they are deposited on a surface demonstrating that porphyrin molecules act as a protection shield for the tubes. This latter property is very interesting in view of applications such as photovoltaic cells or fundamental studies