Efficient thin-film organic solar cells based on pentacene/C60 heterojunctions

We have fabricated an efficient organic photovoltaic cell based on a heterojunction of pentacene and C-60. Photocurrent action spectra exhibit broad light-harvesting throughout the visible spectrum with a peak external quantum efficiency (EQE) of 58+/-4% at short-circuit condition. Modeling studies indicate that this high EQE can be partly attributed to the large exciton diffusion length in the pentacene film as well as efficient dissociation of excitons at the pentacene/C-60 heterojunction. (C) 2004 American Institute of Physics.