Abstract
The objective of this work was to stabilize the active layer of organic solar cells. Indeed, the latter is constituted by an electron donor (D) and an electron acceptor (A). to obtain optimized performances, a phase segregation between the donor and the acceptor need to be set-up. In this case, the charge separation and charge collection are ideal. However, this nanophase segregation is usually not thermodynamically stable. As an example, certain fullerene derivatives when used as an acceptor can diffuse into the layer to form microcrystals which cause photovoltaic conversion efficiencies to drop. It is therefore necessary to stabilize the morphology of this active layer. Very recently, a strategy of crosslinking has been developed by the scientific community. This approach avoids the migration of species by creating an A-A, D-A or D-D network. In this context, we took advantage of organosilicas. The three-dimensional hybrid network, resulting from the hydrolysis-polycondensation of silsesquioxane precursors, allowed us to envisage the three approaches. In a first step, the syntheses and studies of the physicochemical properties of silylated donors and acceptors were carried out.In a second step, these precursors were introduced into solar cells which did not show the performances and the expected stabilities after the hybrid network was formed.Finally, the silylated donor has been exploited in field effect transistors which show interesting performances and exceptional thermal stabilities. In addition, the latter offer the possibility of being immersed in various solvents.