| Conjugated polymer solar cells have the potential to be a cheap, light weight, robust source of solar power and could contribute to solving the energy problems our future faces. The primary limiting factor for commercialization of these devices is the power conversion efficiency, which is governed by the conjugated polymer semiconductor in the active layer of these devices. However, the current state of the art materials are not optimized, and progress in the design of conjugated polymers must be made for these devices to be financially viable. Synthetic modification of the polymer p-type semiconductor is necessary to fully understand the structure-property relationships that govern the underlying principle performance criteria of these polymer photovoltaic cells. By synthesizing new conjugated polymers with a variety of chemical structures, more insight can be gained into the factors that govern the band gap, oxidation and reduction potential, hole mobility, and phase separation behavior of the conjugated polymer is achieved. The culmination of this knowledge allows for the synthesis of new polymer materials which show exceptionally high photovoltaic efficiency of 7%. Additionally, these polymers are able to form exceptionally thick films and still maintain high efficiencies. The exceptional performance of these materials grants a unique insight that will affect polymer design strategies in the future. |
