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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Prof. Alan J. Heeger, University of California, Santa Barbara
2000 Nobel Laureate in Chemistry
Plastic Solar Cells: SelfâAssembly of Bulk Heterojunction Nanoâmaterials by Spontaneous Phase Separation
I will describe the discovery of ultrafast photoinduced electron transfer as the scientific foundation for the creation of a technology for low cost âplasticâ solar cells. This initial charge separation occurs at a time scale two orders of magnitude faster than the first step in photoâsynthesis in green plants. Charge collection at the electrodes is accomplished through selfâassembly of bulk heterojunction (BHJ) nanoâmaterials by spontaneous phase separation.
I will focus on the details of the operating mechanism; the origin of the open circuit voltage (Voc), the role of morphology on the charge separation and charge collection at the electrodes, the need for charge selective buffer layers and the origin of the limitations on the fill factor (FF).
I will summarize recent progress on the performance of solar cells fabricated from semiconducting polymers. We see a clear technology pathway to solar cells with lifetimes and efficiencies required for rooftop applications.
