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Title: Novel oligomeric antennae for luminescent lanthanide cations

Abstract

Organic molecules have long been known to harvest light for the weakly absorbing lanthanide cations; however, in recent decades conjugated oligomers have presented promising photophysical properties. Lanthanide cations have desirable properties for applications that include sharp emission bands, long luminescence lifetimes and resistance to photobleaching. These properties arise partially from the shielded f-orbitals of the lanthanides, which interact weakly with their respective ligand(s). Lanthanides' long lifetimes enable spectral discrimination from background fluorescence through time-resolved measurements. In order to obtain their luminescence properties, lanthanide cations need to be sensitized through an appropriate antenna. Conjugated oligomers provide a platform as antennae with tunable energy of their donating levels. This is obtained by controlling the oligomer chain length (i.e. a more conjugated, longer sequence should have a lower energy of donating singlet and triplet states than a less conjugated, shorter sequence). We have designed and synthesized optically active oligofluorenyl ligands that coordinate and sensitize different luminescent lanthanide cations. Polyfluorenes are well known optically-active polymers. Fluorene derivatives, including its oligomers, often shift the emissive levels to lower energy making it an attractive donor. Fluorene possesses high functionality, allowing it to be incorporated into many applications, such as electroluminescent devices. In our systems, the fluorenemore » backbone harvests the light and transfers the resulting energy to the lanthanide, bound by a coordinating moiety. Thus the energy of the donating level of the fluorene can be tuned, according to the size of the oligomer, to match the energy of the accepting levels of different lanthanides.« less

Authors:
 [1];  [2]; ;  [1];  [1]
  1. (University of Pittsburgh)
  2. (Arkema, Inc., King of Prussia, PA)
Publication Date:
Research Org.:
National Energy Technology Laboratory (NETL), Pittsburgh, PA, and Morgantown, WV
Sponsoring Org.:
USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
913187
Report Number(s):
DOE/NETL-IR-2007-095
TRN: US200802%%584
DOE Contract Number:
None cited
Resource Type:
Conference
Resource Relation:
Conference: ACS 233rd National Meeting, Chicago, IL, Mar. 25-29, 2007
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CATIONS; FLUORENE; FLUORESCENCE; LUMINESCENCE; POLYMERS; RARE EARTHS; TRIPLETS

Citation Formats

Oxley, D.S., Copenhafer, J.E., Edenborn, H.M., Meyer, T.Y., and Petoud, S. Novel oligomeric antennae for luminescent lanthanide cations. United States: N. p., 2007. Web.
Oxley, D.S., Copenhafer, J.E., Edenborn, H.M., Meyer, T.Y., & Petoud, S. Novel oligomeric antennae for luminescent lanthanide cations. United States.
Oxley, D.S., Copenhafer, J.E., Edenborn, H.M., Meyer, T.Y., and Petoud, S. Mon . "Novel oligomeric antennae for luminescent lanthanide cations". United States. doi:.
@article{osti_913187,
title = {Novel oligomeric antennae for luminescent lanthanide cations},
author = {Oxley, D.S. and Copenhafer, J.E. and Edenborn, H.M. and Meyer, T.Y. and Petoud, S.},
abstractNote = {Organic molecules have long been known to harvest light for the weakly absorbing lanthanide cations; however, in recent decades conjugated oligomers have presented promising photophysical properties. Lanthanide cations have desirable properties for applications that include sharp emission bands, long luminescence lifetimes and resistance to photobleaching. These properties arise partially from the shielded f-orbitals of the lanthanides, which interact weakly with their respective ligand(s). Lanthanides' long lifetimes enable spectral discrimination from background fluorescence through time-resolved measurements. In order to obtain their luminescence properties, lanthanide cations need to be sensitized through an appropriate antenna. Conjugated oligomers provide a platform as antennae with tunable energy of their donating levels. This is obtained by controlling the oligomer chain length (i.e. a more conjugated, longer sequence should have a lower energy of donating singlet and triplet states than a less conjugated, shorter sequence). We have designed and synthesized optically active oligofluorenyl ligands that coordinate and sensitize different luminescent lanthanide cations. Polyfluorenes are well known optically-active polymers. Fluorene derivatives, including its oligomers, often shift the emissive levels to lower energy making it an attractive donor. Fluorene possesses high functionality, allowing it to be incorporated into many applications, such as electroluminescent devices. In our systems, the fluorene backbone harvests the light and transfers the resulting energy to the lanthanide, bound by a coordinating moiety. Thus the energy of the donating level of the fluorene can be tuned, according to the size of the oligomer, to match the energy of the accepting levels of different lanthanides.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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