Browsing by Author "Huyal, I. O."
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Unknown Quantum efficiency enhancement in film by making nanoparticles of polyfluorene(Optical Society of America, 2008) Huyal, I. O.; Ozel, T.; Tuncel, D.; Demir, Hilmi VolkanWe report on conjugated polymer nanoparticles of polyfluorene that were formed to exhibit higher fluorescence quantum efficiency in film (68%) and reduce undesired emission peak wavelength shifts in film (by 20 nm), compared to the solid-state polymer thin film made directly out of the same polymer solution without forming nanoparticles. Using the facile reprecipitation method, solutions of poly[9,9-dihexyl-9H-fluorene] in THF were added at different volume ratios to obtain different size distributions of nanoparticle dispersions in water. This allowed us to control the sizedependent optical emission of our polyfluorene nanoparticles. Such organic nanoparticles hold great promise for use as efficient emitters in optoelectronic device applications. (C) 2008 Optical Society of America.Item Unknown White emitting polyfluorene functionalized with azide hybridized on near-UV light emitting diode for high color rendering index(Optical Society of America, 2008) Huyal, I. O.; Ozel, T.; Koldemir, U.; Nizamoglu, S.; Tuncel, D.; Demir, Hilmi VolkanWe develop and demonstrate high-quality white light generation that relies on the use of a single-type simple conjugated polymer of polyfluorene functionalized with azide groups (PFA) integrated on a near-UV LED platform. The high-quality white emission from the polyfluorene is achieved by using the azide functionalization to facilitate cross-linking intentionally when cast into solid-state form. Hybridized on n-UV InGaN/GaN LED at 378 nm, the PFA emitters collectively generate a very broad down-converting photoluminescence at longer wavelengths across the entirety of the visible spectrum, yielding high color rendering indices up to 91. (c) 2008 Optical Society of America.