Indene−C 60 Bisadduct: A New Acceptor for High-Performance Polymer Solar Cells

Polymer solar cells (PSCs) are commonly composed of a blend film of a conjugated polymer donor and a soluble C(60) derivative acceptor sandwiched between an ITO anode and a low-workfunction metal cathode. Poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM) are the most widely used donor and acceptor materials, respectively. However, the low LUMO energy level of PCBM limits the open circuit voltage (V(oc)) of the P3HT-based PSCs to ca. 0.6 V. Here we synthesized a new soluble C(60) derivative, indene-C(60) bisadduct (ICBA), with a LUMO energy level 0.17 eV higher than that of PCBM. The PSC based on P3HT with ICBA as acceptor shows a higher V(oc) of 0.84 V and higher power…