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How solar energy stuffs fluorine into containers

The fluorination in organic solar cells (OSCs) impacts the photoelectric properties of conjugated polymers. Here, two benzo [1,2-c:4,5-c'] dithiophene-4,8-dione (T1) based donor polymers with different numbers of f.
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FAQS about How solar energy stuffs fluorine into containers
Does fluorination improve photoelectric properties of organic solar cells?
Introducing two fluorine atoms enhances hole mobility and improves JSC. The fluorination in organic solar cells (OSCs) impacts the photoelectric properties of conjugated polymers. Here, two benzo [1,2-c:4,5-c'] dithiophene-4,8-dione (T1) based donor polymers with different numbers of fluorine substitutions (F1 and F2) have been investigated.
How do solar cells generate photocurrent?
According to the working principle of solar cells, photocurrent generation should go through those processes. (Guldi and Prato, 2000) Firstly, the active layer absorbs photons and generates excitons. Secondly, the excitons diffuse to the donor–acceptor interface, where they separate to form free charges.
How does fluorination affect optoelectronic properties?
(Zou et al., 2022, Chen et al., 2021) The strong electronegativity of the fluorine element may reduce the HOMO energy level of the molecule, which in turn affects the open-circuit voltage (VOC); the fluorination effect has a significant impact on the optoelectronic properties of the copolymer.
Does fluorination improve OSC efficiency?
While device-performance-enhancing effects by fluorination of the donor units have also been observed, it is less clear that fluorine will always benefit the efficiency of the OSC, as there are several cases where the efficiency drops, in particular with “over-fluorination”, i.e., when too many fluorine substituents are incorporated.