In:
Advanced Functional Materials, Wiley, Vol. 25, No. 38 ( 2015-10), p. 6131-6143
Abstract:
Two angular‐shaped 4,9‐didodecyl α‐aNDT and 4,9‐didodecyl β‐aNDT isomeric structures have been regiospecifically designed and synthesized. The distannylated α‐aNDT and β‐aNDT monomers are copolymerized with the Br‐DTNT monomer by the Stille coupling to furnish two isomeric copolymers, PαNDTDTNT and PβNDTDTNT, respectively. The geometric shape and coplanarity of the isomeric α‐aNDT and β‐aNDT segments in the polymers play a decisive role in determining their macroscopic device performance. Theoretical calculations show that PαNDTDTNT possesses more linear polymeric backbone and higher coplanarity than PβNDTDTNT. The less curved conjugated main chain facilitates stronger intermolecular π–π interactions, resulting in more redshifted absorption spectra of PαNDTDTNT in both solution and thin film compared to the PβNDTDTNT counterpart. 2D wide‐angle X‐ray diffraction analysis reveals that PαNDTDTNT has more ordered π‐stacking and lamellar stacking than PβNDTDTNT as a result of the lesser curvature of the PαNDTDTNT backbone. Consistently, PαNDTDTNT exhibits a greater field effect transistor hole mobility of 0.214 cm 2 V −1 s −1 than PβNDTDTNT with a mobility of 0.038 cm 2 V −1 s −1 . More significantly, the solar cell device incorporating the PαNDTDTNT:PC 71 BM blend delivers a superior power conversion efficiency (PCE) of 8.01% that outperforms the PβNDTDTNT:PC 71 BM‐based device with a moderate PCE of 3.6%.
Type of Medium:
Online Resource
ISSN:
1616-301X
,
1616-3028
DOI:
10.1002/adfm.201502338
Language:
English
Publisher:
Wiley
Publication Date:
2015
detail.hit.zdb_id:
2029061-5
detail.hit.zdb_id:
2039420-2
SSG:
11
