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Information × Registration Number 0224U001349, 0123U102017 , R & D reports Title Formation of semiconductor nanocrystals of various morphology in amorphous and colloidal systems and dependence of their characteristics on the conditions of their fabrication popup.stage_title Head Azhniuk Yurii M., Доктор фізико-математичних наук Registration Date 22-01-2024 Organization Institute of Electronic Physics of the National Academy of Sciences of Ukraine popup.description2  The subject of the study comprises Bi2S3 and SnS2 semiconductor nanocrystals in amorphous As2S3-based matrices, Cu(Ag)–In–S colloidal nanocrystals. The aim of the project is to elucidate the conditions of formation of Bi2S3 and SnS2 semiconductor nanocrystals in amorphous As2S3-based matrices and Cu(Ag)–In–S nanocrystals in colloidal solutions and studies of possibilities of modification of their physical characterisrics by variation of technological parameters of fabrication and external effects. Techniques: optical spectroscopy, photoluminescence spectroscopy, Raman spectroscopy, X-ray diffraction, atomic force microscopy. Raman spectroscopic studies have shown that under illumination of (As1–xBix)2S3 glasses with x0.14 by laser light (532 nm, 40 kW/cm2) the sample surface undergoes photochemical reactions with the formation of structural units containing arsenate AsO43– ions and sulphate SO42– ions formed due to photooxidation. Illumination of As2S3:Sn glasses with Sn content from 2 to 2.7 at. % by above-bandgap light (532 nm, Pexc=40 kW/cm2) is shown to result in the formation of SnS2 crystallites in the illuminated area on the glass surface. This effect of nonthermal character is caused by the glass photosoftening under illumination. Glutathione-capped Cu–In–S nanocrystals were obtained by colloidal synthesis at mild temperature conditions in aqueous solutions, their size-fractioning (from 2.9 to 1.7 nm) was performed. Based on the X-ray diffraction data, the nanocrystal structure was shown to correspond to chalcopyrite type (tetragonal crystal system). A comparative study of the X-ray diffraction data and Raman spectra of Ag–In–S colloidal nanocrystals with those of polycrystals and thermally evaporated films of similar composition, tetragonal and cubic structure of AgInS2 і AgIn5S8 polycrystals, respectively, as well as the amorphous structure of the thermally evaporated films were confirmed. Product Description popup.authors Azhniuk Yuriy Mykolaiovych Voynarovych Ivan Mykolajovych Hasynets Stepan Mykhailovych Gomonnai Oleksandr Vasylyovych Kryshenyk Volodymyr Mykhailovych Lopushansky Vasyl Volodymyrovych Solomon Andrij Mykhailovych popup.nrat_date 2024-01-22 Close