1. Near-IR Absorbing D–A–D Zn-Porphyrin-Based Small-Molecule Donors for Organic Solar Cells with Low-Voltage Loss
- Author
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Pilar de la Cruz, Virginia Cuesta, Rahul Singhal, Ganesh D. Sharma, and Fernando Langa
- Subjects
Materials science ,Absorption spectroscopy ,Organic solar cell ,business.industry ,Analytical chemistry ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Porphyrin ,Acceptor ,0104 chemical sciences ,Active layer ,chemistry.chemical_compound ,chemistry ,Photovoltaics ,Molecule ,General Materials Science ,0210 nano-technology ,business - Abstract
Two D–A–D small molecules with a DPP acceptor core and Zn-porphyrin donor with different electron-donating substituents, namely, 2,6-bis(dodecyloxy)phenyl and 5-hexylthieno[3,2-b]thiophen-2-yl at mesopositions, VC4 and VC5, were synthesized, and their optical and electrochemical properties were investigated. The results reveal that both molecules are suitable as donors for organic solar cells (OSCs) in which PC71BM is employed as the acceptor. Overall power conversion efficiencies of 8.05% (Jsc = 13.83 mA/cm2, Voc = 0.91 V, and FF = 0.64) and 8.89% (Jsc = 16.98 mA/cm2, Voc = 0.79 V, and FF = 0.663) were obtained, respectively. The high Voc value for the VC4-based OSC correlates with the deeper HOMO, whereas the high Jsc value for VC5 may be attributed to the extended absorption spectrum toward the longer wavelength region. Moreover, the relatively high FF value for VC5-based OSCs as compared to the VC4 counterparts may be related to the more balanced charge transport in the active layer, reduced charge re...
- Published
- 2019