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Heterogeneous metal-plasma polymer nanoparticles prepared by means of gas aggregation sources
Štefaníková, Radka ; Kylián, Ondřej (advisor) ; Kousal, Jaroslav (referee)
The field of nanoparticle preparation is nowadays rapidly evolving. Most of the ap- proaches can be classified as wet chemistry techniques. On the other hand, gas aggrega- tion sources offer an alternative, purely physical approach of how to fabricate nanoparti- cles in a controlled and reproducible manner. Many kinds of nanoparticles were already produced in this way, e.g. metallic, metal oxides or plasma polymer nanoparticles. Moreover, as it was demonstrated in recent studies, even heterogeneous nanoparticles by combining more types of materials may be produced by such sources. Among them, an increasing interest is devoted to the metal/plasma polymer nanoparticles. Concerning the production of metal/plasma polymers nanoparticles, the majority of so far published studies focused on the nanoparticles with metallic cores surrounded by a plasma polymer overcoat. Because of this, we decided to investigate a novel two- step deposition procedure for the production of metal/plasma polymer nanoparticles with inverse structure, i.e. nanoparticles with plasma polymer cores covered by metal. This method is based on the gas aggregation technique for plasma polymer nanoparticle fabrication (C:H:N:O in this study) followed by subsequent in-flight coating by sputtered metal (silver, copper and titanium). The production...
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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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Modification of nanoparticles by means of tubular sputtering system
Košutová, Tereza ; Hanuš, Jan (advisor)
The aim of this work is to prepare heterogeneous nanoparticles which means nanoparticles composed of more than one material. Our approach lies in in-flight modification of primary nanoparticles in the tubular sputtering system. Our tubular system contains copper target and we deposit copper onto the flying primary nanoparticles by magnetron sputtering. The main advantage of this approach is independence of fabrication of primary nanoparticles and their subsequent modification. At first we optimized fabrication of nanoparticles by the gas aggregation source on behalf of the next modification. We also characterized conditions in the tubular sputtering system. We found process in the tubular system to be very complex and sensitive to the changes of the operational parameters. There is a strong interaction between flying nanoparticles and the discharge in the tubular system. Due to this interaction the nanoparticles are trapped in the plasma and the deposition rate is pulsing. The result of this work is modification of nickel and silver nanoparticles, preparation of heterogeneous nanoparticles Ni/Cu and Ag/Cu. These heterogeneous nanoparticles vary in composition, shape and size according to the conditions in the tubular system. We also successfully prepared Janus nanoparticles which are interesting for their...
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Heterogeneous metal-plasma polymer nanoparticles prepared by means of gas aggregation sources
Štefaníková, Radka ; Kylián, Ondřej (advisor) ; Kousal, Jaroslav (referee)
The field of nanoparticle preparation is nowadays rapidly evolving. Most of the ap- proaches can be classified as wet chemistry techniques. On the other hand, gas aggrega- tion sources offer an alternative, purely physical approach of how to fabricate nanoparti- cles in a controlled and reproducible manner. Many kinds of nanoparticles were already produced in this way, e.g. metallic, metal oxides or plasma polymer nanoparticles. Moreover, as it was demonstrated in recent studies, even heterogeneous nanoparticles by combining more types of materials may be produced by such sources. Among them, an increasing interest is devoted to the metal/plasma polymer nanoparticles. Concerning the production of metal/plasma polymers nanoparticles, the majority of so far published studies focused on the nanoparticles with metallic cores surrounded by a plasma polymer overcoat. Because of this, we decided to investigate a novel two- step deposition procedure for the production of metal/plasma polymer nanoparticles with inverse structure, i.e. nanoparticles with plasma polymer cores covered by metal. This method is based on the gas aggregation technique for plasma polymer nanoparticle fabrication (C:H:N:O in this study) followed by subsequent in-flight coating by sputtered metal (silver, copper and titanium). The production...
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Modification of nanoparticles by means of tubular sputtering system
Košutová, Tereza ; Hanuš, Jan (advisor)
The aim of this work is to prepare heterogeneous nanoparticles which means nanoparticles composed of more than one material. Our approach lies in in-flight modification of primary nanoparticles in the tubular sputtering system. Our tubular system contains copper target and we deposit copper onto the flying primary nanoparticles by magnetron sputtering. The main advantage of this approach is independence of fabrication of primary nanoparticles and their subsequent modification. At first we optimized fabrication of nanoparticles by the gas aggregation source on behalf of the next modification. We also characterized conditions in the tubular sputtering system. We found process in the tubular system to be very complex and sensitive to the changes of the operational parameters. There is a strong interaction between flying nanoparticles and the discharge in the tubular system. Due to this interaction the nanoparticles are trapped in the plasma and the deposition rate is pulsing. The result of this work is modification of nickel and silver nanoparticles, preparation of heterogeneous nanoparticles Ni/Cu and Ag/Cu. These heterogeneous nanoparticles vary in composition, shape and size according to the conditions in the tubular system. We also successfully prepared Janus nanoparticles which are interesting for their...
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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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Modification of nanoparticles by means of tubular sputtering system
Kretková, Tereza ; Hanuš, Jan (advisor) ; Matoušek, Jindřich (referee)
The aim of this work is to prepare heterogeneous nanoparticles which means nanoparticles composed of more than one material. Our approach lies in in-flight modification of primary nanoparticles in the tubular sputtering system. Our tubular system contains copper target and we deposit copper onto the flying primary nanoparticles by magnetron sputtering. The main advantage of this approach is independence of fabrication of primary nanoparticles and their subsequent modification. At first we optimized fabrication of nanoparticles by the gas aggregation source on behalf of the next modification. We also characterized conditions in the tubular sputtering system. We found process in the tubular system to be very complex and sensitive to the changes of the operational parameters. There is a strong interaction between flying nanoparticles and the discharge in the tubular system. Due to this interaction the nanoparticles are trapped in the plasma and the deposition rate is pulsing. The result of this work is modification of nickel and silver nanoparticles, preparation of heterogeneous nanoparticles Ni/Cu and Ag/Cu. These heterogeneous nanoparticles vary in composition, shape and size according to the conditions in the tubular system. We also successfully prepared Janus nanoparticles which are interesting for their...
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