Z. He et al., The efficient blue photoluminescence of pyrazolo-[3,4-b]-quinoline derivatives and the energy transfer in polymer matrices, J LUMINESC, 86(1), 2000, pp. 1-14
The photophysical properties of a series of pyrazolo-[3,4-b]-quinoline deri
vatives have been studied in solution and as dopants in several polymer mat
rices (polycarbonate (PC), polystyrene (PS), poly(methyl methacrylate) (PMM
A) and poly(N-vinyl carbazole) (PVK)). In solution these materials exhibit
a high quantum yield for fluorescence at 450 nm of between 76% and 100%. Th
e variation in substitution of the pyrazoloquinoline core of this series of
materials has little effect on the photophysical properties in solution or
in the polymer films. The materials exhibit little concentration quenching
as the photoluminescence efficiencies remain high even at high dopant conc
entration. However, there is significant interaction of the dopant with the
polymer matrices causing modification of the dopant absorption and excitat
ion spectra and faster fluorescence decays. In the case of the PVK matrix t
here is evidence for the existence of a rapid energy transfer pathway from
the polymer to the dopant. The results show that pyrazoloquinolines are a p
romising class of materials for use in optical and optoelectronic applicati
ons. (C) 2000 Elsevier Science B.V. All rights reserved.