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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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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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Dynamics of drying of sessile droplets in dependence on the surface wettability
Štefaníková, Radka ; Kylián, Ondřej (advisor) ; Shukurov, Andrey (referee)
Wettability is one of the key parameters that govern interaction between solid objects and their surrounding environment. In this work wettability of two kinds of materials was investigated - untreated and plasma treated polyether ether ketone and nanostructured C:F thin films deposited either onto a smooth substrate or on substrates seeded with nanoparticles. In the first case the main focus was given to the evaluation of dependence of wettability and water droplet drying dynamics on the plasma treated PEEK on storage time. It was found that plasma treatment induces changes in surface morphology and in chemical composition that in turn results in dramatic increase of surface wettability as well as in alteration in drying dynamics. It was shown that whereas chemical composition and wettability gradually approach properties observed on untreated PEEK, the drying dynamics, namely disappearance of the constant contact angle phase, is temporally stable. In the second case the main emphasis was given to the investigation of the effect of surface nanoroughness and its character on wettability of produced samples. It was found that when the base layer was composed from nanoparticles of the same kind, the surfaces exhibited higher values of water contact angles as compared to C:F films deposited onto smooth...
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