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Information × Registration Number 0213U003845, 0111U007513 , R & D reports Title Development of new-generation luminescent materials - organo-inorganic composites for light-emitting structures. Section A. Development of methods of preparation of organo-inorganic hybride nanocomposites based on conductive conjugated polymers. popup.stage_title Head Pokhodenko Vitaly Dmytrovych, Registration Date 01-02-2013 Organization L.V.Pysarzhevsky Institute of Physical Chemistry of National Academy of Science of Ukraine popup.description2 Aqueous dispersions of nanocomposites based on PEDOT:PSS and MoO3 were prepared. It was found that a 4-times increase of the PSS content in nanocomposites results in amelioration of their quality (homogeneity, mechanical properties, adhesion to a substrate) with only a slight decrease in the conductivity. Addition of organic solvents to aqueous dispersions of such nanocomposite results in an increase in transparency and conductivity of the later-produced films. Hybride nanocomposites oif PEDOT:PSS and silver nanowires were prepared. In such nanocomposites agglomeration of polymer macromolecules takes place resulting in formation of particles with the size up to 5 micron. Addition of the silver nanowires to the aqueous PEDOT:PSS suspension does not lower the transparency of the later-produced films but results in a 3-5 fold decrease in conductivity. New methods of synthesis of CdS and CdSe quantum dots were developed using stabilizers - cadmium(II) complexes with mercaptoacetic acid and hydrazine allowing to achieve a manifold increase in the photoluminescence intensity. A strong dependence between the temperature and luminescence intensity of the CdS quantum dots was found, resulting from thermally activated dissociation of surface Cd(II) complexes with the stabilizers and formation of aqua-complexes, which act as the sites of radiationless electron-hole recombination. Model light-emitting diodes based on the synthesized CdS quantum dots incorporated into polymer films were produced and tested. The LEDs emit electroluminescence in the visible spectral range in broad bands centered at around 520 nm (gelatin films) and 560 nm (chitosan film) at application of the voltage higher than 10 V. Methods of synthesis of new tris(3-pyridilpyrazolyl)borate complexes of therbium (III) and europium (III) were developed, the complexes exhibiting efficient luminescence with the quantum yields of 30 % and 10 %, respectively. On the basis of the complexes the model LEDs were prepared emitting electroluminescence at application of the voltage of around 9 V.5481 Product Description popup.authors Конощук Наталія Володимирівна Кучмій Степан Ярославович Павліщук Віталій Валентинович Посудієвський Олег Юлійович Походенко Віталій Дмитрович Раєвська Олександра Євгенівна Строюк Олександр Леонідович popup.nrat_date 2020-04-02 Close