Abstract
New organic semiconducting molecules containing diketopyrrolopyrrole and thiophene units were designed to investigate the influence of effective conjugation length on the performance of organic photovoltaics made with [6,6]-phenyl-C61-butyric acid methyl ester. New D-A-D-A-D type molecules (where; D = donor, A = acceptor) such as ter- and quarter-thiophene bridged diketopyrrolopyrrole dimers were synthesized with different numbers of conjugative units. The field-effect mobilities of these molecules were determined by fabricating thin film transistors. The new molecules displayed moderately high mobility between 3.6 × 10-2 and 1.1 × 10-2 cm2 V-1 s-1 without a thermal annealing process for TT(BTDPP)2 and QT(BTDPP)2. The TT(BTDPP)2 molecule possesses a longer effective conjugation length (c.f. QT(BTDPP)2) and shows a high carrier mobility. When employing the ter- and quarter-thiophene bridged diketopyrrolopyrrole dimers as donor molecule in combination with [6,6]-phenyl-C61-butyric acid methyl ester [TT(BTDPP)2:PC61BM = 1:0.8 w/w], the photovoltaic cell provides the highest power conversion efficiency of 3.76%.
Original language | English |
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Pages (from-to) | 7-14 |
Number of pages | 8 |
Journal | Dyes and Pigments |
Volume | 108 |
DOIs | |
Publication status | Published - 2014 Sept |
Bibliographical note
Funding Information:This research was supported by National Research Foundation of Korea ( NRF2012R1A2A1A01008797 ) and by Priority Research Centers Program through the NRF funded by the Korean Ministry of Education, Science and Technology ( NRF20120005860 ).
Keywords
- Bulk heterojunction
- Diketopyrrolopyrrole
- Effective conjugation length
- Organic photovoltaics
- Organic thin film transistor
- Power conversion efficiency
ASJC Scopus subject areas
- General Chemical Engineering
- Process Chemistry and Technology