Formation and characterization of phthalocyanine dimer/C60 solar cells

Organic solar cells with μ-oxo-bridged gallium phthalocyanine dimer (GaPc dimer) and fullerene were produced by an evaporation method. A device based on the GaPc dimer provided a conversion efficiency of 4.2×10–3%, which is better compared to a device based on phthalocyanine monomer. Dimerization effect was discussed with a molecular orbital calculation, and the crystalline phases of the present solar cells were investigated by X-ray diffraction. Further improvement of the efficiency was discussed on the basis of the experimental results.