Device architectures in organic photovoltaics

The various device structures used in organic polymer solar cells are reviewed. The operating principles behind these devices are explained in order to provide the reasoning behind the different structures. The incorporation of nanostructures into both bilayer and bulk heterojunction devices to improve exciton separation, charge transport, and light absorption is discussed. Novel ideas such as electrospun fibers and supramolecules are also covered. Finally, the impact of these structures on overall efficiency is evaluated.