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OLOMOUC – Densification Urbaine – Urban Consolidation
Bystroň, Tomáš ; Jung, Adam (referee) ; Koleček, Ivan (advisor)
The aim of the project is to complete the city on two levels. Within the meaning of densifying the development, i.e. filling the now empty site with a building that exploits the potential of the site, and of complementing the functional structure of the city with a building that would bring new opportunities for the city. The undevelopment of the site is based on the historical context. Previously, the site was the place of the fortification system of the city of Olomouc and the Morava River was used as a natural barrier; after the abolition of the fortification system, most of the vacant strip was built over, but some empty spaces still remain, as it is in the case with the site. At the same time, the city of Olomouc has basically no city architect and all efforts for architectural debate, exhibitions or development are scattered in a decentralised way. The city also has a very small elementary art school, which is out of proportion to the music school located near the location of my design. The project therefore aims to meaningfully complete to city.
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Investigation of new catalysts for polymer membrane fuel cells
Fiala, Roman ; Matolín, Vladimír (advisor) ; Bystroň, Tomáš (referee) ; Napporn, Teko Wilhelmin (referee)
Fuel cells are a promising alternate power source of electricity. Despite of sig- nificant improvement that was reached by research throughout recent decades, the technology is not still ready to large scale commercial use. The catalyst of fuel cell (FC) should be still investigated due to fact that the only reliable functional catalyst is Platinum, a noble and expensive metal, which makes the use of this technology not competitive. In this thesis, investigation of Platinum doped ceria catalyst and its modification prepared by physical technique of deposition which is magnetron sputtering is presented. The catalyst was studied using standard sur- face analytic techniques (PES, SEM, AFM, XANES) as well as electrochemical measurement (CV, PEIS). The principal part of this thesis reports direct analyses of catalyst in fuel cell using an individually designed fuel cell test station. Con- sidering the high power density (PD) about 1 W cm−2 and substantially higher specific power per gram of Platinum (SP) 1.6 kW mg−1 in comparison with com- mercial Pt-Ru/Pt-C reference catalyst and additionally the relatively longtime stability, the sputtered Platinum doped cerium oxide based catalyst was found a suitable catalyst for PEM FC. Moreover, possible substitution of Pt and CeO2 by other elements was shown. Beside of...
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Investigation of Ir(Ox)-Ru(Oy) thin-film catalysts for oxygen evolution reaction in proton exchange membrane water electrolyzers
Hrbek, Tomáš ; Kúš, Peter (advisor) ; Bystroň, Tomáš (referee)
The main focus of this master thesis is the investigation of the anode catalysts for the Proton Exchange Membrane Water Electrolyzers (PEM-WEs). PEM-WEs play a pivotal role in the hydrogen economy concept as they allow water decomposition into oxygen and hydrogen. However, their operation requires expensive noble metal catalysts, i.e., iridium or platinum. This issue has yet to be solved to mass-produce PEM-WEs. Consequently, our main objective is to reduce the amount of iridium on the anode of PEM-WEs. We addressed this objective by two distinct approaches: morphological and chemical. With the morphological approach, plasma etching of the membrane and the magnetron sput- tering of CeO2 served to increase the membrane's active surface. Hence we improved the catalysts utilization. With the chemical approach, we focused on the catalyst itself. Thus, we replaced the pure iridium catalyst with a bimetallic iridium-ruthenium one. Therefore, the activity of the catalyst was enhanced while its price got reduced. To ex- plain and describe the catalyst's behavior, we used various electrochemical methods and surface analysis techniques. Finally, we combined both approaches to obtain one active, stable, and low-iridium-loading anode catalyst for PEM-WE.
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Investigation of new catalysts for polymer membrane fuel cells
Fiala, Roman ; Matolín, Vladimír (advisor) ; Bystroň, Tomáš (referee) ; Napporn, Teko Wilhelmin (referee)
Fuel cells are a promising alternate power source of electricity. Despite of sig- nificant improvement that was reached by research throughout recent decades, the technology is not still ready to large scale commercial use. The catalyst of fuel cell (FC) should be still investigated due to fact that the only reliable functional catalyst is Platinum, a noble and expensive metal, which makes the use of this technology not competitive. In this thesis, investigation of Platinum doped ceria catalyst and its modification prepared by physical technique of deposition which is magnetron sputtering is presented. The catalyst was studied using standard sur- face analytic techniques (PES, SEM, AFM, XANES) as well as electrochemical measurement (CV, PEIS). The principal part of this thesis reports direct analyses of catalyst in fuel cell using an individually designed fuel cell test station. Con- sidering the high power density (PD) about 1 W cm−2 and substantially higher specific power per gram of Platinum (SP) 1.6 kW mg−1 in comparison with com- mercial Pt-Ru/Pt-C reference catalyst and additionally the relatively longtime stability, the sputtered Platinum doped cerium oxide based catalyst was found a suitable catalyst for PEM FC. Moreover, possible substitution of Pt and CeO2 by other elements was shown. Beside of...
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Low Platinum Content Thin Film Catalysts for Hydrogen Proton Exchange Membrane Fuel Cells
Václavů, Michal ; Matolín, Vladimír (advisor) ; Bystroň, Tomáš (referee) ; Neitzel, Armin (referee)
Novel type of catalyst for proton exchange membrane fuel cells anode is demonstrated. It is based on magnetron sputtered Pt-CeO2 a Pt-Sn-CeO2 mixed oxides. It is shown, that these materials allow to significantly decrease amount of platinum in the anode catalyst. The preparation method yields high amount of platinum in ionized form, especially Pt2+ , which is related to the high activity. Stability of these catalytic layers were investigated under conditions similar to fuel cell anode (humidified hydrogen at elevated temperature). Also interaction of hydrogen a water under UHV conditions were studied, demonstrating high stability of the Pt2+ species. In the last part of the work sputtered Pt-Co mixed catalyst were investigated to be used in the PEMFC cathode. It is demonstrated that at right conditions, the sputtered alloy catalyst improves mass activity on cathode by factor more than two.
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Morphology of model catalysts in electrolyte environment
Keresteš, Jiří ; Mysliveček, Josef (advisor) ; Bystroň, Tomáš (referee)
The aim of this thesis is preparation of inverse model catalyst CeOx/Pt(111) and its investigation using combination of surface physics methods and electrochemistry. New electrochemical cell was designed and built for electrochemical experiments. CeOx/Pt(111) samples were prepared and studied in UHV using STM and XPS methods. After that, samples were transferred to the electrolyte environment and studied by means of cyclic voltammetry and AFM. For high surface coverage of CeOx, new reaction was observed. We have identified this reaction as a combination of the reduction of cerium(IV) oxide by interaction with hydrogen adsorbed on the Pt(111) surface and oxidation of cerium(III) oxide by dissociative adsorption of water molecules. Powered by TCPDF (www.tcpdf.org)
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