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Information × Registration Number 0211U000796, 0110U006230 , R & D reports Title Invesetigation of optical properties and tunnel processes of carriers (excitons) in two-phases semiconductors nanosystem of type "core@shell" C1@C2 (С1 = SiO2, C2 = ZnO, CdS, ZnSe, ZnS and other) that are promising blocks for materials of nanophysics and electronics. popup.stage_title Head Brodyn M.S., Registration Date 24-02-2011 Organization Institute of physics NASU popup.description2 The investigation objects - core-shell heteronanoparticles with the core of spherical particles SiO2 given sizes (O 200?300 nm) and shell from ZnO and CdS quantum dots. The goal of the work - development of the technology of the ZnO and CdS quantum dots ensembles obtaining on the spherical SiO2 templates forming core-shell heteronanoparticles, study of the structural and morphological properties of the new optical materials, investigation of the exciton processes in such structures and determination of the energy spectrum of the charge carries (excitons). The SiO2/ZnO and SiO2/CdS core-shell structured particles with the core of amorphous monodisperse 200 nm SiO2 spheres and shell of nanocrystals with various sizes has been obtained by one-step low-temperature crystallization from a nonaqueous solutions. The structure, chemical composition and geometrical parameters of the heteronanoparticles experimental samples in the form of suspensions and thin films on the metal substrates have been investigated by the methods of electron microscopy and chemical analysis. It was shown that heteronanoparticles on the basis of SiO2 spheres have ideal spherical form, keep the individuality independent on composition and structure of the functional shell. So, it indicates of absence of heteronanoparticles sintering at the optimized synthesis parameters and considerable decrease of degree of heteronanoparticles aggregation in the solutions. Dispersion in the sizes of the SiO2/ZnO heteronanoparticles obtained was less then 7% and determinate by the dispersion value of the SiO2 particles. The optical and low-temperature luminescence spectra obtained of the such structures testify about significant quantum-dimensional effects at low temperatures as well as exciton channels of radiative recombination are dominant. This is a good evidence of high quality crystalline structure of the samples and low number of surface states in these objects. Product Description popup.authors Єрмолаєва Юлія Володимирівна Бондар Микола Володимирович Бродин Михайло Семенович Матвєєвська Неоніла Анатолієвна Толмачов Олександр Володимирович popup.nrat_date 2020-04-02 Close