Journal
JOURNAL OF MATERIALS CHEMISTRY C
Volume 7, Issue 39, Pages 12217-12230Publisher
ROYAL SOC CHEMISTRY
DOI: 10.1039/c9tc03577j
Keywords
-
Funding
- National Natural Science Foundation of China [51573154, 51673031, 51573107]
- Natural Science Foundation of the Jiangsu Higher Institutions of China [18KJA480001]
- Youth Science and Technology Foundation of Sichuan Province [2013JQ0032]
- Foundation of State Key Laboratory of Polymer Materials Engineering [sklpme2014-3-05]
- Natural Science Foundation of Jiangsu Province [BK20141151]
- Hunan 2011 Collaborative Innovation Center of Chemical Engineering & Technology with Environmental Benignity and Effective Resource Utilization
Ask authors/readers for more resources
To reveal the influences of introducing various end-capping units onto small-molecule (SM) donors, in this article, 2-octylthio-thiophene (TS), 2-octyl-thiazole (TZ) and 2-octylthiothiazole (TZS) are strategically selected as end-capping units to combine with a fluorinated 2,2 '-bithiophene (FBT) core and thiophene-flanked diketopyrrolopyrrole (TDPP) units as electron acceptors to afford three novel D(A-Ar)(2) type SM donors, namely FBT(TDPP-TS)(2), FBT(TDPP-TZ)(2) and FBT(TDPP-TZS)(2). The structure-property relationships provoked by slight changes in the terminal groups were systematically evaluated. In particular, TZS end-units make FBT(TDPP-TZS)(2) possess better molecular stacking, higher mobility and better miscibility in the blend with PC71BM in comparison with the other two SMs. As a result, the introduction of TZS end-groups has been found to enhance the open-circuit voltage (V-oc), short circuit current density (J(sc)) and fill factor (FF) simultaneously. After optimization, an outstanding power conversion efficiency (PCE) of 8.91% with a V-oc of 0.80 V, a J(sc) of 16.75 mA cm(-2) and a FF of 66.93% was obtained for the FBT(TDPP-TZS)(2) based device, which is among the top values of the D(A-Ar)(2) type single junction small molecular BHJ-OSCs. Our results obtained here indicate that strategic hetero-substitution of end-capping units in D(A-Ar)(2) type SMs is an efficient strategy to improve photovoltaic performance.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available