Communication
ChemComm
2
3
an organic solvent with a high boiling point of 259 1C, was Electronics under the Global Frontier Research Program of the
added to the polymer semiconductor–chloroform solution. The Ministry of Science, ICT and Future Planning, Korea. The
rest of the device fabrication was the same. The polymer films authors thank the Pohang Accelerator Laboratory for providing
were annealed at the optimal thermal annealing temperature. the synchrotron radiation sources at 3C and 9A beam lines used
Fig. 3d shows the transfer characteristics of PFETs prepared in this study.
using 1.2 v% CN in chloroform. The CN-processed PNDI-RO
FETs displayed a significantly enhanced electron mobility of up Notes and references
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À1 À1
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À1 À1
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2
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s , but the performance improvement is less
(
using the CN additive from 0.958 to 1.02 nm for PNDI-OR and
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PFETs, where the PNDI-RO FETs exhibited more stable operation
than did the PNDI-OR FETs. The better bias-stress stability of
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structure of the side chains (see Fig. S5, ESI†). Moreover, all-
polymer bulk-heterojunction solar cells with all-polymer blend
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In conclusion, oligo(ethylene glycol)-incorporated hybrid linear
side chains were designed and synthesized with n-channel NDI-
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the attached side chains, without disrupting the rigidity of the
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behavior was observed for the resulting copolymers. In parti-
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1
.64 cm V
s
with a high on–off current ratio of 10 . These
2
results demonstrate that hybrid side chains using oligo(ethylene
glycol) are promising new solubilizing groups for high-performance
organic semiconductor materials.
This work was supported by a grant (Code No. 2011–0031628
and 2013M3A6A5073172) from the Center for Advanced Soft
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Chem. Commun.
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