Correlation of hole mobility, exciton diffusion length, and solar cell characteristics in phthalocyanine/fullerene organic solar cells

The authors investigated heterojunction organic solar cells composed of different metal phthalocyanines (MPcs, M=Fe, Co, Ni, Cu, and H-2)/fullerene (C-60) and compared the solar cell characteristics with the field-effect hole mobilities (mu(h)) and exciton diffusion length (L-ex) of the different MPcs. They observed that the short circuit current (J(SC)) is linearly dependent on the mu(h) of the MPcs, except for ZnPc. They also estimated the L-ex of the MPcs by creating a line of best fit using the action spectra of the external quantum efficiency in the solar cells and found that J(SC) is closely correlated with the L-ex of the MPcs. (c) 2007 American Institute of Physics.