ICMUB - News

Vendredi 28 septembre 2007 : Conf de Dirk Guldi, Erlangen-Nürnberg (Allemagne)

Carbon based electron donor acceptor hybrids for solar energy conversion

Carbon-based nanomaterials are currently under active investigations for producing innovative materials, composites, and electronic devices of greatly reduced size. Among the wide variety of carbon materials (i.e. fullerene, single and multi wall carbon nanotubes, carbon fibers, carbon nanoonions, and single wall carbon nanohorns), single wall carbon nanotubes (SWNT) and single wall carbon nanohorns (SWNH) are of particular interest.

The structure of SWNT is conceptualized by wrapping a one-atom-thick layer of a graphene sheet, that is, an interlinked hexagonal lattice of carbon atoms, into a seamless cylinder. The diameter of most SWNT is close to 1 nm, with a tube length that might be many thousands of times larger. Importantly, based on different arrangements, SWNT possess different electrical properties (i.e., semiconductor or metallic), which are the result of the electrons moving differently in the tube depending on the SWNT arrangement.
SWNH, on the other hand, are typically constituted by tubes of about 2-5 nm of diameter and 30 to 50 nm long, which associate each other to give rise to round-shaped aggregates of 100 nm of diameter. Their large surface areas (1006-1464 m2g-1) and inner nanospaces (0.47-1.05 mL/g) are of great importance, since they ensure a great affinity with organic electron donors and make them promising candidates for electrical and chemical solar energy conversion.

In this respect, I will highlight the opportunities that rest on carbon nanostructures – much beyond the well-studied fullerenes – within the context of electron transfer reactions in novel chemical and light driven systems. In particular, I will survey our approaches to design, characterize, and examine the potential for practical applications of super- and supramolecular association of carbon-based nanomaterials with electron donors towards stable donor-acceptor nanohybrids and nanoconjugates within the context of light induced charge separation and solar energy conversion. Important are the impact, the benefits and some of the promises that evolve from electron transfer reactions with carbon nanostructures on i) the stabilization of radical ion pair states, ii) multi electron catalytic reactions and iii) photoelectrochemical / photovoltaic solar energy conversion.

Télécharger l'affiche (pdf, 48 Ko).
Contact : Jean-Claude Chambron

ICMUB (UMR 5260) - University of Burgundy - Dijon (France)