Abstract : The photovoltaic effect is one of the options which significantly developed during the last years in order to find an alternative to non-renewable energy production. In order to reduce the manufacturing costs of photovoltaic devices, a solution consists in replacing silicon by organic materials. The organic solar cells are an emerging technology which ambitions the supply of more flexible solar cells in all the meanings of the term: mechanics, manufacture, electrooptic properties. A challenge with which research is confronted today is obtaining stable and soluble organic materials which absorb at near-infrared wavelengths. This PhD work which was carried in the Technological Research Team CSPVP of the University of Angers aims at taking up the challenge. The first part of our work is devoted to the use of new fullerene derivatives. In order to improve absorption of the fullerene C60 and/or to seek for possible alternatives to the PCBM, new compounds were synthesized. The new derivatives can be divided into: C60-PDI dyads (R=OPhtBu, Cl), cyclopropano  fullerenes and cyclopropano  fullerenes. These fullerene derivatives were incorporated in the photo-active layers of solar cells containing poly (3-hexylthiophene) (P3HT) polymer. All were used in solar cells for which we could specify the relation between the molecular structure and the photovoltaic performances via the morphology of the active layer. Additional studies were carried out in order to corroborate the photovoltaic results with the physicochemical properties of the materials. The second part is devoted to physicochemical studies carried out on different carbon nanotubes mono-layers (SWCNT) functionalized by ester group. These functionalized nanotubes offer a better dispersion in organic solvents. They were studied and compared at various concentrations in solar cells containing P3HT: PCBM. Complementary work was carried out on derivatives of poly (phenylene vinylene), polythiophene, and carbazol attached to the C60 core which were deposited on ITO/PEDOT: PSS substrates by electropolymerisation. Conclusion is a review the parameters which contribute directly to the photovoltaic performances of the studied cells.