Novel fullerene acceptors: synthesis and application in low band gap polymer solar cells

One novel C60 derivative F1 and its corresponding C70 derivative F2 were designed and synthesized by the [4+2] cyclic addition reaction. The optical, electrochemical and photovoltaic properties of them were carefully characterized. The LUMO energy levels of them are about 0.06 eV higher than that of PCBM. The power conversion efficiency of the polymer solar cells based on P3HT as donor and F1 and F2 as acceptors, reached 3.63% and 3.35%, respectively. When using PBDTTT-C to replace P3HT as a donor, the performance of F1 and F2 based devices reached 3.00% and 5.07%, respectively.