Journal of the American Chemical Society
Article
EXPERIMENTAL SECTION
ACKNOWLEDGMENTS
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General. Steady-state photoabsorption spectroscopy was per-
formed using a Jasco V-570 UV−vis spectrophotometer. Solar
spectrum and white light spectrum from a Xe-flash lamp were
measured through an optical fiber using an Ocean Optics HR4000
spectrometer. Note that the sensitivity is limited from 300 to 1000 nm,
the output intensity of which is not calibrated. The time profile of the
WLP from a Xe-flash lamp was measured using a Si pin photodiode
(Hamamatsu Inc. S1722-22).
This work was supported by the Precursory Research for
Embryonic Science and Technology (PRESTO) program of
the Japan Science and Technology Agency (JST), Tenure
Track Program at the Frontier Research Base for Global Young
Researchers of JST and Osaka University, and a KAKENHI
grant from the Ministry of Education, Culture, Sports, Science
and Technology (MEXT) of Japan.
Materials. PCBM (purity >99.5%) was obtained from Frontier
Carbon Inc. PBDTTT-CF was purchased from One-Material Inc.
PCDTBT, PCPDTBT, and PBDTTPD were synthesized in
accordance with previous reports,34−46 the details of which are given
in the Supporting Information. Solvents were purchased from Kishida
Kagaku Corp. unless otherwise noted and were used as-received
without further purification.
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ASSOCIATED CONTENT
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S
* Supporting Information
Synthesis of the monomers and polymers and Supporting
Figures S1−S4. This material is available free of charge via the
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AUTHOR INFORMATION
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Corresponding Author
(28) Mihailetchi, V. D.; Xie, H.; de Boer, B.; Koster, L. J. A.; Blom, P.
W. M. Adv. Funct. Mater. 2006, 16, 699−708.
(29) Son, H. J.; Wang, W.; Xu, T.; Liang, Y.; Wu, Y.; Li, G.; Yu, L. J.
Am. Chem. Soc. 2011, 133, 1885−1894.
Notes
The authors declare no competing financial interest.
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dx.doi.org/10.1021/ja309524f | J. Am. Chem. Soc. 2012, 134, 19035−19042