All-organic photovoltaic cells
Materials for organic and nanocristaline photovoltaic cells with coloring

An organic photovoltaic cell is a device comprising an organic active layer (based on polymers or small molecules) on the order of a hundred nm thick, inserted between two electrodes. One of these must be semi-transparent to allow light penetration. The active layer consists of two materials, one an electron acceptor and the other an electron donor (figure 1). The photovoltaic process is initiated by the absorption of a photon by the electron donor and/or electron acceptor, leading to the formation of an excited state corresponding to the creation of a bonded electron-hole pair called an exciton. Unlike inorganic cells, the electron-hole pair constituting this exciton is tightly bound, due to the strong Coulombic...