Search academic texts

Information × Registration Number 0219U004960, 0115U004201 , R & D reports Title Creatiоn of the new functional systems based on heterogeneous ensembles of metaloxide nanoparticles. popup.stage_title Head Gorban Oksana Oleksandrivna, Кандидат хімічних наук Registration Date 17-12-2019 Organization Donetsk Institute of Physics @ Engineering named after O.O.Galkin NAS of Ukraine popup.description2 Objects of study - oxide nanopowders ZnO, ZrO2 and CeO2 doped ZnO and systems modified by silver compounds, their structure, surface state, phase stability, optical properties, heteroassemblies and photocatalytic activity. The aim of the work (stage V) is the developing of a principles of new technologies for producing heterogeneous ensembles of metal oxide nanoparticles using physical and chemical actions to control their structure and properties. Methods of method - X-ray diffraction and phase analysis (XRD), electron paramagnetic resonance (ESR), UV-visible spectroscopy, liquid chromatography, equipment for UV phenol degradation, time resolution microwave conductivity (TRMC). The methodology of synthesis of multicomponent ZnO-based composite systems with different types of matrix defects doped by a small amount of Al2O3, ZrO2, CeO2 oxides and additionally doped silver compounds was developed. The effect of synthesis mode (nature of precursors, type and amount of dopant, temperature) on the structure and optical properties of the multicomponent or composite material that was studied by the methods of XRD, EPR and UV-visible spectroscopy. In the work a comparative analysis of ZnO structures with different type of defects in the matrix (VZn or VO), systems based on these defective ZnO matrices which additionally doped by Al2O3, ZrO2, CeO2 in the amount of 0.1 mol. % and additionally decorated with silver compounds was carried out. It is shown that the catalytic activity of a material depends on the type of defects in the structure of zinc oxide and targeted formation of oxygen vacancies increases the photoactivity of this material by up to 40%. At the same time, the addition of a small amount of wide-gap oxides to the ZnO matrix influences the formation of additional defects in the matrix, which makes it possible to control the state of the surface. This approach is useful for forming composite structures with metallic particles. Thus, it was shown that the addition of ZrO2 in ZnO with oxygen vacancies allows the formation of a composite of oxide NPs / silver NPs, while the addition of CeO2 to the system in ZnO with oxygen vacancies allows the formation of a composite oxide NPs / NPs AgCl@Ag. The connection between the structure of the composite material and its optical and photocatalytic properties is considered. It is shown that by varying the structure of the composite system it is possible to further increase the efficiency of the catalyst by 30%. Scientific significance is the identification factors that affect the characteristics, behavior and formation processes and functionality of complex systems Zn0,999M0,001O / Ag-containing compound (M = Al, Zr, Ce) under conditions of chemical action (precursor and dopant type) and physical action of temperature. Practical value: technological techniques for the synthesis of composite heterogeneous systems based on zinc oxide (additionally doped wide-band oxides to control defects, surface condition) and decorated silver compounds are used to control the activity of the nanoparticles upon their receipt, as well as their optical properties. The relevance and socio-practical relevance of the work are due to the potential for the use of synthesized powders and heterogeneous ensembles based on them in paints and polymers, as well as the component for the creation of material with catalytic properties for air purification systems of the H2020 project. Product Description popup.authors Акхозов Леонід Афанасійович Горбань Сергій Васильович Даніленко Ігор Анатолійович Лакуста Маргарита Валеріївна Шило Артем Володимирович popup.nrat_date 2020-04-02 Close