Improved efficiency of polymer-fullerene bulk heterojunction solar cells by the addition of Cu(II)-porphyrin-oligothiophene conjugates.

Ternary organic photovoltaic devices were prepared through the addition of small amounts of metalloporphyin-terthiophenes to two established low bandgap polymer:fullerene blends. The methodology afforded a PCDTBT:PC 71 BM-based device that displayed an initial power conversion efficiency of 5.1%, an increase of 16% when compared to the binary blend. Among the range of metalloporphyrins considered in this study, the Cu(II)-porphyrin derivatives were found to result in the most significant efficiency improvements. [ABSTRACT FROM AUTHOR]