Synthesis and photophysical properties of functional macromolecules from short Single Walled Carbon Nanotubes (sSWNT), (4,4'-diphenylvinyl)-sSWNT and (alkylazaxanthone)-sSWNT.

ROBERTO MARTIN; LILIANA B. JIMENEZ; J. C. SCAIANO; HERMENEGILDO GARCIA

Burlingame, California, Estados Unidos

Congreso; The 34th Meeting of the American Society for Photobiology; 2008

American Society for Photobiology

Nanomaterials, including nanotubes, have been the focus of considerable attention for their magnificent mechanical and electrical properties. They also exhibit promising physical properties for various biological applications such as transporters in living cells.Covalent functionalization of short single walled carbon nanotubes (sSWNT) has been used extensively to modify their physical and chemical properties. The ability to respond to an external stimulus, particularly electronic excitation, is a highly desirable property that could generate functional materials such as sensors, relays, photovoltaic devices, etc. In our work, sSWNT have been linked to either 4,4?-diphenyl vinyl (DPV-sSWNT) or azaxanthone (AZAX-sSWNT) moieties. The resulting derivatives have been characterized by transmission spectroscopy and their structures more firmly established by liquid-phase NMR, IR and Raman spectroscopy. The photophysical properties of DPV-sSWNT and AZAX-sSWNT were investigated by laser flash photolysis. We observe an increase in the intensity of the short-lived transient signal with increasing oxygen concentration for DPV-sSWNT. The intermolecular interaction between excited sSWNT and ?free? aromatic chromophores (DPV and Azax) was also studied. In the case of Azax-sSWNT, it has been investigated the influence of alkyl bridge, between sSWNT and Azax, in the transient species. Also, in this system was studied the photophysical properties changing sSWNT to other different linker between azaxanthone chromophores.