ИСТИНА

The double-caged [60]fullerene n-decyl ester (d[60]FDe) and the n-decyl [60]fulleroproline ([60]FprDe) have been synthesized and tested as an electron acceptors for polymer-fullerene bulk heterojunction solar cells. Optical absorption, solubility, and photovoltaic properties of d[60]FDe and [60]FprDe are reported. Solar cells with the device configuration ITO/PEDOT:PSS/P3HT: d[60]FDe([60]FprDe)/Ca/Al have been investigated with the reference cells based on the P3HT:[60]PCBM blends. We study the influence of donor/acceptor ratio and the effect of thermal annealing on the device performance. The P3HT:d[60]FDe as-prepared devices show the same open-circuit voltage and the fill factor as the P3HT:[60]PCBM ones, but the short-circuit current is significantly more. However, after thermal annealing the open-circuit voltage and the fill factor of P3HT:d[60]FDe devices are considerably less. The power conversion efficiency of P3HT:d[60]FDe devices with the best weight ratio of 1:0.4 without annealing is about 1.5% under illumination by AM1.5G (100 mW/cm2) radiation.