Photovoltaic properties of bisazomethine dye thin films

Photovoltaic properties of bisazomethine dye (DE2) in vacuum-deposited thin films were examined for use in Schottky-type photovoltaic cells (ITO/DE2/Al). We measured dark and photo current–voltage characteristics and determined photocurrent action spectra. We confirmed the p-type semiconductor property of DE2 thin films evidenced by the formation of the Schottky barrier at the DE2/Al interface. We further found a relatively high incident photon to electron conversion efficiency comparable to that of metal phthalocyanine thin films in devices having the same structure. These results demonstrate that DE2 thin film is a candidate for a photocarrier-generating material in organic solar cells.