This work deals with the preparation and characterization of organic solar cells based on novel classes of soluble molecular donors. The first chapter is devoted to the study of bulk heterojunction organic solar cells based on poly(3-hexylthiophene) and a soluble derivative of fullerene C60. This type of device is used as a model system to analyze the various experimental parameters involved in the fabrication and optimization of organic solar cells. The experimental procedures defined on the basis of these studies have been subsequently applied to the evaluation of two classes of molecular donors namely diketopyrrolopyrrole (DPP) and boron dipyrromethene (BODIPY). The work on DPP-based donors involved the fabrication of various series of bilayer and bulk heterojunction solar cells. The results of these investigations have led to interesting performances and to a better understanding of structure-properties relationships in this family of molecular donors. The last part of this work concerned the study and realization of solar cells based on an original class of molecular donors derived from BODIPY. The characterization of the electronic properties of different families of BODIPYs as well as the preparation and study of several series of solar cells have led to important progress, and power conversion efficiencies among the highest reported so far for molecular BHJ solar cells based on soluble C60 derivative have been obtained. Furthermore, first evidences of cooperative effects in molecular BHJ using multiple donors have also been presented.
