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Information × Registration Number 0214U000453, 0113U000862 , R & D reports Title Development and optimization of effective methods for the synthesis of nano-sized crystals of CdTe, a study of their luminescent properties and the development of highly efficient light-emitting devices based on them. popup.stage_title Head Tomashik V. M., Доктор хімічних наук Registration Date 05-03-2014 Organization Institute of Semiconductor Physics of National Academy of Sciences of Ukrain popup.description2 Report of scientific research work: 45 p., 24 fig., 3 tabl. The objects of research are the processes of quantum dots synthesis, nanocrystals transfer methods in polymer matrix, the study of photo-and electroluminescence spectra and optical absorption of incorporated nanocrystals in a solid state matrix. The purpose is to develop the effective methods of introducing CdTe nanocrystals from colloidal solutions in the solid matrix and study the photo-and electroluminescence spectra and optical absorption of obtained materials. The investigation methods are the photoluminescence spectra in a wide temperature range (T = 4.2-300 K) using laser excitation sources and Raman spectra. Anotation: The new methods for quantum dots (QDs) CdTe synthesis in aqueous colloidal solution have been developed. The methods of impurities extraction from the initial solution and separating it into fractions with smaller spread in size have been improved. The sedimentary deposition allows dividing the original polydisperse colloidal solution into fractions with CdTe nanocrystals (NC) sizes variation within fractions of less than 1 nm, with a gradual NC concentration decrease in each subsequent fraction has been established. For the different factions with the increasing size of CdTe NC is clearly observed a gradual batohromnyy shift of photoluminescence bands, which is consistent with the optical absorption data and it is a result of the band gap dependence on the crystal size. The transfer methods of CdTe NC in polymer matrix have been developed. The using of gelatin as a stabilizer at the same time and the matrix in which it is possible to obtain stable for a long time highly luminescent nanosized cadmium telluride composites specified shape has been proposed. The bi-modal distribution determined by the sizes of CdTe QDs in polymer matrix as a result of prolonged aging at room temperature, that is shown in the PL spectra in the form of two bands (2.17 eV i 2.41 eV).has been found. The perspective of CdTe NC practical application and the creation on their basis of highly efficient light-emitting devices in which the wavelength of the radiation can be controlled only resizing of NC without changing their chemical composition has been shown. It is possible to get the white light sources, characterized by low power and high strength if incorporated in solid state matrix the NC of different sizes. The expected suppositions about the research object development - The results will be used to create a solid matrices with incorporated nanocrystal materials with satisfactory fluorescent characteristics, for the purpose of their application as the light-emitting devices active elements. Product Description popup.authors Будзуляк С.І. Вахняк Н.Д. Демчина Л.А. Калитчук С.М. Капуш О.А. Корбутяк Д.В. Крюченко Ю.В. Мазарчук І.О. Морозовська В.Й. Стратійчук І.Б. Томашик З.Ф. Тріщук Л.І. popup.nrat_date 2020-04-02 Close