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Synthesis and photocatalytic applications of titanium dioxide
Solný, Tomáš ; Drbohlavová, Jana (referee) ; Vlček,, Jozef (referee) ; Ptáček, Petr (advisor)
V práci je zkoumán vliv podmínek na průběh hydrolýzy alkoxidů titanu a vlastností připravovaných nanočástic oxidu titaničitého s důrazem na teplotu a množství vody přítomné v systému. Připravované hydrolyzáty alkoxidů titanu a nanočástice oxidu titaničitého připravené z hydrolyzátů jsou studovány metodami XRD, DTA – TGA, SEM – EDS, BET a PCCS. Nanočástice magnetitu byly syntetizovány pomocí precipitační reakce z roztoku Mohrovy soli a jejich krystalová struktura, velikost a povrchové vlastnosti byly sledovány s vyhodnocením vlivu teploty a při modifikaci povrchu polykarboxyletherovým superplastifikátorem. Pro upevnění TiO2 na povrch magnetitu byla použita kombinovaná metoda aplikace vybraných nanočástic TiO2 s hydrolýzou TiO2 pomocí alkoxidů titanu za účelem přípravy fotokatalyticky aktivního core-shell práškového katalyzátoru s vylepšenými vlastnostmi adsorpce na povrchu. Studovány byly možnosti aplikace TiO2 na povrch Mn-Zn feritu, kdy byl studován vliv depozice tenkých vrstev C a Au na morfologii povrchu. Fotokatalytická aktivita vybraných připravených materiálů byla studována pomocí dekompozice methylenové modři v roztoku a par isopropanolu a ethanolu rozkládaných pomocí Mn-Zn feritu v experimentálním chemickém reaktoru s magnetickým polem stabilizovaným ložem nosiče katalyzátoru.
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Vertically aligned CdS nanorod arrays for solar cell applications
Hroch, Daniel ; Lednický, Tomáš (referee) ; Drbohlavová, Jana (advisor)
This thesis describes the deposition of nanoparticles into nanoporous alumina templates. Nanoparticles of cadmium sulphide were chosen thanks to wide band gap of 2,45 eV. CdS is desired semiconductor promising better efficiency when comes to solar radiation conversion to useful energy. Theoretical part consists of explanation of photovoltaic principles, band-gap theory of materials, currently available technologies to manufacture solar cells and their efficiencies. Next part introduces the approaches of manufacturing nanoporous templates from aluminium (Anodized Aluminium Oxide, AAO) in details together with options to deposit cadmium sulphide into these structures. There is also brief description of deposition based on vacuum filtration. Experiments were made in Laboratory of Microsensors and Nanotechnologies at Faculty of Electrical Engineering and Communication in Brno University of. The experimental chapter describes manufacturing process of AAO and deposition via vacuum filtration. Samples were evaluated by Scanning Electron Microscopy.
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Biomolecules influence on optical properties of deposited quantum dots
Roček, Vojtěch ; Mravec, Filip (referee) ; Drbohlavová, Jana (advisor)
This thesis is focused on creation of quantum dots of titanium dioxide with help of nanoporous alumina mask and on funcionalization of their surface in purpose to increase the quantum yield of its. This thesis is devided into 6 main chapters, where the glossary topic of quantum dots creation process and ways of practical usage of these quantum dots are made. The theoretical knowledge is used for creation of titanium dioxide quantum dots, which was deposited by gold and funcionalized with glutation. The results are shown and discussed in the end of this work.
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Biofunctionalization of water soluble CdTe quantum dots
Šibíková, Anna ; Drbohlavová, Jana (referee) ; Pekárková, Jana (advisor)
This bachelor thesis is focused on the research on biofuncionalization of water-soluble glutathione modified CdTe quantum dots (QDs). The thesis is divided into three parts. The first part is a theoretical introduction to the QDs and their synthesis, modifications and applications in biology together with an introduction to proteins and bioconjugation of QDs and BSA. In the second part I present the experimental results of water-soluble glutathione modified CdTe-GSH QDs preparation. The QDs were cleaned and bioconjugated with BSA at different concentrations. This is described in the third part of the thesis. I also discuss the obtained experimental results in the frames of available literature.
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Biofunctionalization of deposited quantum dots
Jakubechová, Jana ; Venerová, Tereza (referee) ; Drbohlavová, Jana (advisor)
The goal of this bachelor thesis is to functionalize the deposited quantum dots (QDs). QDs are prepared thanks to nanoporous alumina template in process of anodic oxidation of Ti film on a silicon wafer followed with modification of gold in process of pulse deposition. The final objective is the subsequent observation of fluorescent properties changes. QDs shows outstanding optical characteristics which can be used for labeling and imaging in biological systems. Thanks to their unique fotostability, they allow long term observation of biomolecules.
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Preparation of nanostructures using nanoporous template
Dzuro, Matej ; Hrdý, Radim (referee) ; Drbohlavová, Jana (advisor)
The aim of the work described in this paper is to prepare electrochemically an optical sensor consisting of TiO2 quantum dots (QDs) using nanoporous Al2O3 template in the first step and to modify the surface of QDs with gold layer by evaporation process, again using nanoporous template, in the second step. This easy, cheap and rapid approach provides homogenous and highly ordered distribution of both nanostructures on substrate. The final objective is to characterize the physical parameters and fluorescent properties of TiO2/Au sensor designed for optical detection of biomolecules such as DNA and proteins.
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TiO2 nanoporous surfaces and their properties
Roček, Vojtěch ; Urbánková, Kateřina (referee) ; Drbohlavová, Jana (advisor)
This thesis is focused on creation nanostructured surfaces of titanium dioxide and the use of photocatalytic activity of these surfaces for antimicrobial applications. The work is divided into nine main chapters, in which the literature search for producing these surfaces, the principle of photocatalysis and their typical specifics was made. These theoretical findings are then used to form such layers, analyzing their chemical and physical properties and practical verification of their antimicrobial activity. This work experimentally verified processes to ensure the increase of antimicrobial activity. The results and findings are discussed in the conclusion.
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Electrophotocatalytic wather disinfection
Štefancová, Eva ; Drbohlavová, Jana (referee) ; Veselá, Mária (advisor)
This work focuses on the photoelectrocatalytic water disinfection by applying electrical voltage onto an electrode system. Working electrode consist of electrical conductor covered by thin film TiO2, because of its very important photoactivity. Disinfection effect was monitored on Gram-negative bacteria E. coli under different conditions. Inactivation of bacterial cells in contamined aqueous solution, first experiment was observed only with presence of oxygen, later reactor was irradiated with UV-A compact blacklight with intensity of 4 mW• m-2 or electrical voltage of 1V was applied to electrode. By adding both effects at the same time I was verifying photoelectrocatalysic water disinfection on chosen microorganism.
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Titania mesoporous films fabricated by material printing
Chludilová, Markéta ; Drbohlavová, Jana (referee) ; Dzik, Petr (advisor)
Thesis deals with the creation of thin layers of a porous titanium dioxide. The solutions for the formation of thin layers were prepared using a solgel method by mixing TTIP, polyethylene glycol of molecular weight 1500 and dimethyl, layers were subsequently printed by material printer to glass substrate and calcinated at 450 °C for 2,5 hours. Optical and SEM microscopy was used to observe structure of individual layers. Samples, that showed the greatest porosity, were subsequently studied by electrochemical measurments and by photocatalytic aktivity determined via hydroxylation of coumarin.
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