Publication details for Professor Andy MonkmanRothe, C & Monkman, A (2002). Dynamics and trap-depth distribution of triplet excited states in thin films of the light-emitting polymer poly (9,9-di(ethylhexyl)fluorene). Physical Review B 65(7): 4.
- Publication type: Journal papers: academic
- ISSN/ISBN: 1098-0121
- Keywords: PI-CONJUGATED POLYMERS; PHOSPHORESCENCE; EXCITATIONS; DIODES
Author(s) from Durham
We study the behavior of the phosphorescence and delayed fluorescence
of the light-emitting polymer poly[9,9-di(ethylhexyl)fluorene] with
different excitation intensities at low temperatures. The results
indicate a limited number of potentially occupied energy sites (traps)
for triplet-excited states. From analysis of temperature-dependent
intensity measurements, we demonstrate the Gaussian distribution of
these energy traps and determine an average trap depth of 4.4 +/- 0.1
meV combined with a half-width of 4.5 +/- 0.3 meV. We also observe a
redshift of the phosphorescence spectrum with increasing temperature,
but no concomitant spectral narrowing.