The values of absorption and fluorescence maxima, extinction coefficients and fluorescence quantum yield of these new heterocyclic fluorophores were obtained and they show highlighting interesting photophysical properties.
Fluorescent spectral studies indicated that soluble PBNME was a good blue-light emitter with maximum emission at 415 nm and fluorescence quantum yield of 0.15, while solid-state PBNME film showed its emission centered at 380 nm.
While polymer 5 shows a fluorescence maximum at λe=568 nm (with a fluorescence quantum yield of Φf=7%), a total fluorescence quenching was observed in 8. Far better photovoltaic performance was obtained from solar cells (set up: ITO/PEDOT PSS/active layer/LiF/Al; active layer consisting of 5 or 8b as donor and PCBM as acceptor in a 1 3 ratio by weight) designed from 5 than from 8b.
Studies of the luminescence behaviour of alizarin, purpurin and pseudopurpurin as aluminium (Al3+) complexes have shown that, whereas purpurin-Al3+ and pseudopurpurin-Al3+ complexes show emission maxima at 551/595 and 542/583 nm respectively, alizarin-Al3+ has an emission maximum at c. 640 nm and a fluorescence quantum yield nearly 50 times lower than the equivalent purpurin complex [29].
The InP/ZnS core/shell QDs with maximum fluorescence peak at ~ 530 nm, superior fluorescence quantum yield of 60.1%, and full width at half maximum of 55 nm were applied as an emission layer to fabricate multilayered QD-LEDs.
For the optical properties, the green fluorescent InP/ZnS core/shell QDs with superior fluorescence quantum yield of 60.1% and full width at half maximum of 55 nm were used as an emission layer to prepare multilayered QD-LEDs.
In addition, the bathochromic shift of the maximum absorption (λabs) and the increase in the fluorescence quantum yield (ΦF) were observed by the introduction of phenyl group onto the silyl moieties.
In solution, the spectral position of the absorption maximum, the size of Stokes shift, and the fluorescence quantum yield are considerably affected by ortho-substitution in three or four ortho-positions.
Solutions of these polymers in chloroform exhibit violet fluorescence, having maximum emission wavelength in the range of 412 425 nm and fluorescence quantum yield in the range of 0.11 0.26.
Their characteristics include : 16 nm diameter, 94% size monodispersity, extinction coefficient of 800.000 M-1 cm-1 at 638 nm, and a fluorescence quantum yield of 80% with a full width at half maximum of 28 nm.
