Exciton regeneration at polymeric semiconductor heterojunctions.
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TLDR
It is shown via E-field-dependent time-resolved photoluminescence spectroscopy that excitons that have undergone charge separation at a heterojunction can be efficiently regenerated.Abstract:
Control of the band-edge offsets at heterojunctions between organic semiconductors allows efficient operation of either photovoltaic or light-emitting diodes. We investigate systems where the exciton is marginally stable against charge separation and show via E-field-dependent time-resolved photoluminescence spectroscopy that excitons that have undergone charge separation at a heterojunction can be efficiently regenerated. This is because the charge transfer produces a geminate electron-hole pair (separation 2.2 –3.1 nm) which may collapse into an exciplex and then endothermically (EA � 100–200 meV) back transfer towards the exciton. DOI: 10.1103/PhysRevLett.92.247402read more
Citations
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References
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Book
Electronic Processes in Organic Crystals and Polymers
Martin Pope,Charles E. Swenberg +1 more
TL;DR: The first edition of the Electronic Processes of Organic Crystals, published in 1982, became the classic reference in the field and has been expanded to cover the major theoretical and experimental advances over the last fifteen years.