The results of the X-ray diffraction suggest that the dπ-spacing distance for poly(diethylhexyloxy benzo dithiophene-dioctyloxy dithiophene dibenzophenazine (PBDTAFQ) (dπ=3.89Å) was smaller than poly(diethylhexyloxy benzo dithiophene-dioctyloxy dithiophene diphenyl Qu) (PBDTAQ) (dπ=4.36 Å) because of fused-phenyl ring derivative. As a result, PBDTAFQ displayed a higher absorbance at the UV–vis absorption spectra in the film state. And, as a consequence, PBDTAFQ showed an improved short current density (JSC) in organic photovoltaic cells. The PBDTAFQ:PC70BM blend devices that were fabricated exhibited a power conversion efficiency of 3.4%.
- Tae Ho Lee
- Min Hee Choi
- Doo-Kyung Moon
