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In-flight modification of nanoparticles by chemically active plasma
Libenská, Hana ; Hanuš, Jan (advisor)
Title: In-flight modification of nanoparticles by chemically active plasma Author: Hana Libenská Department: Department of Macromolecular Physics Supervisor: Mgr. Jan Hanuš Ph.D., Department of Macromolecular Physics Abstract: This diploma thesis is focused on a fabrication of the iron nanoparticles using the gas aggregation source with a planar magnetron and their in flight modification by chemically active plasma. The modification of the nanoparticles is based on a radiofrequency glow discharge, that takes place right after the nanoparticles flew out of the gas aggregation source. Nanoparticles are prepared in an argon atmosphere in which a small amount of the n-hexane has been admixed. This n-hexane impurity caused an increase in a deposition rate and higher time stability. The modification takes place in a glow discharge containing a pure argon, or in the mixtures of argon with n-hexane, ethylendiamine, hydrogen or nitrogen. Prepared nanoparticles were characterized using the X-ray photoelectron spectroscopy, scanning and transmission electron microscopy, X-ray diffraction and other techniques. The main aim of this work was to study the influence of the additional discharge on the iron nanoparticles. The chemical composition of the nanoparticles was measured immediatelly after their deposition without...
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In-flight modification of nanoparticles by chemically active plasma
Libenská, Hana ; Hanuš, Jan (advisor) ; Kohout, Jaroslav (referee)
Title: In-flight modification of nanoparticles by chemically active plasma Author: Hana Libenská Department: Department of Macromolecular Physics Supervisor: Mgr. Jan Hanuš Ph.D., Department of Macromolecular Physics Abstract: This diploma thesis is focused on a fabrication of the iron nanoparticles using the gas aggregation source with a planar magnetron and their in flight modification by chemically active plasma. The modification of the nanoparticles is based on a radiofrequency glow discharge, that takes place right after the nanoparticles flew out of the gas aggregation source. Nanoparticles are prepared in an argon atmosphere in which a small amount of the n-hexane has been admixed. This n-hexane impurity caused an increase in a deposition rate and higher time stability. The modification takes place in a glow discharge containing a pure argon, or in the mixtures of argon with n-hexane, ethylendiamine, hydrogen or nitrogen. Prepared nanoparticles were characterized using the X-ray photoelectron spectroscopy, scanning and transmission electron microscopy, X-ray diffraction and other techniques. The main aim of this work was to study the influence of the additional discharge on the iron nanoparticles. The chemical composition of the nanoparticles was measured immediatelly after their deposition without...
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Deposition of ultrathin films on polymers
Libenská, Hana ; Hanuš, Jan (advisor) ; Kousal, Jaroslav (referee)
Thin metal films deposited on the polymer substrates are of fundamental importance for the formation of conductive structures on the surfaces of the polymers. In the case of discontinuous layers of silver or copper, so-called anomalous absorption occurs in the visible range of the spectrum. This phenomenon can be used to create different sensors, eg. based on surface enhanced Raman spectroscopy. In this work, the deposition of discontinuous Ag and Cu layers on PEEK and PET polymer foils and glass and polished silicon was used studied. The magnetron sputtering was chosen for deposition at very low pressure and the effect of pressure on the growth of these films was investigated. It was found that at a pressure of 0.2 Pa the copper layers on the two polymers grew almost smooth, while the island structure appeared at a pressure 1.2 Pa. In the case of Ag deposition, the island structure of the layer appeared already at a pressure of 0.2 Pa, and differences in the growth of the Ag films in dependence of the the substrate were observed.
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