کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
78905 49344 2012 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Solution-processable oligothiophenes with solubilizing β-alkyl groups for organic photovoltaic cells
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Solution-processable oligothiophenes with solubilizing β-alkyl groups for organic photovoltaic cells
چکیده انگلیسی

Two linear-type π-conjugated small molecules based on thiophene and benzothiadiazole, β-DH5TB(1) and β-DH5TB(2), were synthesized using the Suzuki coupling reaction to have β-substituted solubilizing alkyl groups. The solubility of β-DH5TBs was significantly improved by changing the direction of the alkyl group compared to α-substituted oligothiophene (α-DH5TB). The relationship between the alkyl substitution pattern and the photovoltaic properties was investigated by measuring the optical and electrochemical properties and the film morphology. Among them, the 4-hexyl substituted β-DH5TB(2) showed the lowest optical band gap and HOMO level together with a red-shifted broad UV absorption. In addition, a high degree of molecular alignment was also observed in β-DH5TB(2), indicative of good charge transport. The β-DH5TB(2) film showed higher field-effect mobility (μFET) of 6.28×10−4 cm2 V−1 s−1 than β-DH5TB(1) film. Owing to the improved solubility, two of the synthesized β-DH5TBs could be used as donor materials in solution-processed organic photovoltaic cells (OPVs), whereas the α-DH5TB:PC71BM blend film showed no photovoltaic properties due to the poor solubility of α-DH5TB. The improved absorption and molecular alignment of the β-DH5TB(2) yielded a device efficiency (0.98%) higher than that of β-DH5TB(1).


► The solubilizing β-alkyl groups were introduced into a linear-type π-conjugated oligothiophene.
► β-DH5TBs showed improved solubility making them good candidates for solution-processed OFET and OPV devices.
► A higher PCE (0.98%) of β-DH5TB(2):PC71BM film than β-DH5TB(1):PC71BM film.
► The improved optical and electrochemical properties and good molecular alignment of β-DH5TB(2).

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Solar Energy Materials and Solar Cells - Volume 107, December 2012, Pages 165–174
نویسندگان
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