Fluorinated Zinc and Copper Phthalocyanines as Efficient Third Components in Ternary Bulk Heterojunction Solar Cells

Fluorinated zinc and copper metallophthalocyanines MPcF48 are synthesized and incorporated as third component small molecules in ternary organic solar cells (TOSCs). To enable the high performance of TOSCs, maximizing short-circuit current density (J(SC)) is crucial. Ternary bulk heterojunction blends, consisting of a polymer donor PTB7-Th, fullerene acceptors PC70BM, and a third component MPcF48, are formulated to fabricate TOSCs with a device architecture of ITO/PFN/active layer/V2O5/Ag. Employing copper as metal atom substitution in the third component of TOSCs enhances J(SC) as a result of complementary absorption spectra in the near-infrared region. In combination with J(SC) enhancement, suppressed charge recombination, improved exciton dissociation and charge carrier collection efficiency, and better morphology lead to a slightly improved fill factor (FF), resulting in a 7% enhancement of PCE than those of binary OSCs. In addition to the increased PCE, the photostability of TOSCs has also been improved by the appropriate addition of CuPcF48. Detailed studies imply that metal atom substitution in phthalocyanines is an effective way to improve J(SC), FF, and thus the performance and photostability of TOSCs.

Automated summary

In this study, fluorinated zinc and copper metallophthalocyanines were synthesized and incorporated as the third component small molecules in ternary organic solar cells (TOSCs). Using copper as a metal atom substitution in TOSCs enhanced the short-circuit current density, improved photostability, and resulted in a 7% enhancement of power conversion efficiency.