Antonio Cravino

Theodulf Rousseau; Antonio Cravino; Thomas Bura; Gilles Ulrich; Raymond Ziessel; Jean Roncali

Molecular bulk heterojunction solar cells with a power conversion efficiency of 1.70% have been fabricated using as donor BODIPY dyes with complementary light-harvesting properties.

Sophie Roquet; Rémi de Bettignies; Philippe Leriche; Antonio Cravino; Jean Roncali

Tetrahedral conjugated systems involving four conjugated oligothiophene chains fixed onto a central silicon node (1, 2) have been synthesized and used as donor materials in hetero-junction solar cells. Bilayer solar cells have been realized by thermal evaporation of compounds 1 and 2 as donors and N,N′-bis-tridecylperylenedicarboxyimide as an acceptor. Comparison of the performances of these devices to those of a reference system based on dihexylterthienyl (H3T) shows that despite comparable effective conjugation lengths, the 3D compounds 1 and 2 lead to a power conversion efficiency four–five times higher, suggesting better absorption of the incident light and better hole transport properties. Whereas fabrication of bulk hetero-junction with H3T was prevented by the lack of film forming properties, a prototype bulk hetero-junction based on compound 2 as the donor and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as the acceptor has been realized. A short-circuit current density of 1.13 mA cm−2 and a power conversion efficiency of 0.30% has been measured under AM 1.5 simulated solar irradiation at 80 mW cm−2.

Antonio Cravino

This letter analyzes the influence of the energy of the highest-energy occupied molecular orbital (HOMO) and the single occupied molecular orbital (SOMO) (i.e., the low-energy polaronic level) of different electron donors (D) on the open circuit voltage (VOC) value delivered by bilayer and bulk-heterojunction solar cells containing fullerenes as acceptor (A). The analysis further confirms that the VOC of these devices scales with the energy difference between the HOMO of the D and the lowest-energy unoccupied molecular orbital of the A. As observed, a better relationship is obtained if the SOMO energy of the D—extracted from photoinduced absorption spectra—is considered.

Olivier Alévêque; Pierre Frère; Philippe Leriche; Tony Breton; Antonio Cravino; Jean Roncali

OFETs built from extended TTF derivatives containing N-methylpyrrole, furan, thiophene and benzene with meta or para linkages as spacers are presented. The aromatic spacer plays a crucial role in the characteristics and stability of the OFETs. The less conjugated derivative with a meta-benzene moiety as spacer has the best mobility, with a higher on/off ratio and strongly enhanced stability in air.

Philippe Leriche; David Aillerie; Sophie Roquet; Magali Allain; Antonio Cravino; Pierre Frère; Jean Roncali

3D-conjugated systems based on oligothiophene segments grafted on a phosphorus or on a phosphine oxide node have been synthesized. Under Stille coupling conditions, bromide terminated thienyl phosphine derivatives undergo a breaking of the phosphorus-carbon bond attributed to a ligand exchange with the Pd catalyst. The electronic properties of the new compounds have been analyzed by UV-vis and fluorescence spectroscopy and cyclic voltammetry.

Sophie Roquet; Antonio Cravino; Philippe Leriche; Olivier Alévêque; Pierre Frère; Jean Roncali

Jean Roncali; Philippe Leriche; Antonio Cravino

Theodulf Rousseau; Antonio Cravino; Emilie Ripaud; Philippe Leriche; Sandra Rihn; Antoinette De Nicola; Raymond Ziessel; Jean Roncali

Antonio Cravino; Philippe Leriche; Olivier Alévêque; Sophie Roquet; Jean Roncali

Antonio Cravino; Sophie Roquet; Olivier Alévêque; Philippe Leriche; Pierre Frère; Jean Roncali