Improving power conversion efficiency of polymer solar cells by doping copper phthalocyanine

To improve the efficiency of polymer solar cells, a third component copper phthalocyanine (CuPc) was added into poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) binary blends, the normal and inverted ternary blend solar cells were fabricated. The results showed that the incorporation of the CuPc into P3HT:PCBM binary blends not only broadened the absorption range of solar spectrum but also improved the charge separation and transport properties. As a result, a higher short circuit current and fill factor were obtained for ternary blend devices, especially, the power conversion efficiencies (PCEs) of the ternary blend solar cells increased 19% compared with the PCEs of binary blend solar cells.