Slow energy transfer in self-doped β-conformation film of steric polydiarylfluorenes toward stable dual deep-blue amplified spontaneous emission
Author(s)
Type
Journal Article
Abstract
Exciton behavior is crucial for improving the optoelectronic property of a light-emitting conjugated polymer. Herein, the photoexcitation dynamics of exciton migration and energy transfer in a self-doped β-conformation film of the polydiarylfluorenes (poly[4-(octyloxy)-9,9-diphenylfluoren-2,7-diyl]-co-[5-(octyloxy)-9,9- diphenylfluoren-2,7-diyl], PODPF) are demonstrated. Compared to the first generation of the β-conformation polyfluorene, poly(9,9-dioctylfluorene) (PFO), energy transfer occurs in PODPF β-conformation films in a time period of ≈150 ps, much longer than those of the PFO ones (<5 ps), associated with the effective intrachain energy transfer (few hundred picoseconds), rather than interchain Förster energy transfer (a few picoseconds). Similar to PFO, the PODPF β-conformation also displays well-resolved vibronic emission peaks at 20 K, attributed to the planar and rigid conformation. Interestingly, a residual 0-0 band emission of nonplanar conformation chain segments (435 nm, 2.85 eV) at 20 K also further confirms the exciton migration from the amorphous state to the β-conformation domain in PODPF films. Therefore, the stable dual amplified spontaneous emission (ASE) behavior of the PODPF self-doped films at 461 nm (2.69 eV) and 483 nm (2.57 eV), originates from the individual amorphous and β-conformation domains.
Date Issued
2022-01-01
Date Acceptance
2021-07-14
Citation
Advanced Optical Materials, 2022, 10 (1)
ISSN
2195-1071
Publisher
Wiley
Journal / Book Title
Advanced Optical Materials
Volume
10
Issue
1
Copyright Statement
© 2021 Wiley-VCH GmbH
Subjects
AGGREGATION
BEHAVIOR
beta-conformation
CRYSTALLINE
dual amplified spontaneous emission
ELECTROLUMINESCENCE
ELEMENTS
energy transfer
Materials Science
Materials Science, Multidisciplinary
MOLECULAR DESIGN
Optics
PHASE
Physical Sciences
polydiarylfluorenes
Science & Technology
Technology
time-resolved PL spectroscopy
TRANSPORT
Publication Status
Published
Article Number
2100723
Date Publish Online
2021-10-18