|
|
Organické polovodiče
Tebich, Ivan ; Macháček, Martin (oponent) ; Boušek, Jaroslav (vedoucí práce)
Práce pojednává o využití fotovoltaického jevu k výrobě elektrické energie prostřednictvím solárních článků. Zkoumá princip fotovoltaického jevu v organických strukturách. Dále uvádí základní druhy konstrukcí organických solárních článků a hodnotí jejich vlastnosti. V experimentální části je práce zaměřena na charakterizaci tenkovrstvých struktur z fotovodivých organických materiálů.
|
|
|
Technologies using organic materials
Galbička, Tomáš ; Chmela, Ondřej (oponent) ; Hubálek, Jaromír (vedoucí práce)
There are sumarized some of the basic organic materials for produce of organic parts. Two types of theese materials are introduced PPV and PFV and their derivatives, which tuning their resulting properties in area of electrical, optical, chemical, and thermal parameters. There is designed and created system for mechanical bending of adhesive SMD devies on flexible printed circuit board and compared properties of some conducting adhesives.
|
|
|
Organic materials for organic field-effect transistors and electrochemical transistors
Stříteský, Stanislav ; Weis,, Martin (oponent) ; Boušek, Jaroslav (oponent) ; Weiter, Martin (vedoucí práce)
This work is aimed to the study of the properties of organic semiconducting materials with a focus on their conductivity and mobility of charge carriers. The main goal of this thesis is to elucidate the relationship between the chemical structure of organic semiconductors and their properties. The theoretical part of this work is focused on the basics of organic semiconductors, charge transport and a review of the properties of organic semiconducting materials which have led to their application in field-effect and electrochemical transistors. The experimental part presents the overview of the materials used, the methods for their preparation and characterization methods. Within the result part, several methods for thin-film preparation were developed or optimize and subsequently their effect on the performance of organic field-effect transistors were studied. The relevant properties of novel organic semiconducting materials were characterized and discussed with focus on the charge carrier mobility. The biocompatibility of several organic semiconductors were characterized and discussed. Electrical properties, stability and biocompatibility of electroactive polymer inks based on PEDOT:PSS was characterized and discussed with respect to their possible application in bioelectronics. Finally, the organic bioelectronic sensor for detection of the physiological response of cardiomyocytes based on studied materials were constructed.
|
|
|
Organické polovodiče na povrchu tolopogického izolátoru
Hrubá, Daniela ; Průša, Stanislav (oponent) ; Procházka, Pavel (vedoucí práce)
Tato bakalářská práce se zabývá využitím topologického izolantu Bi2Se3 jako substrátu pro depozici různých typů organických molekul. Příprava substrátu probíhala metodou exfoliace v podmínkách ultravysokého vakua (UHV). Pro depozici molekul pentacenu, kyseliny 4,4'-bifenyl-dikarboxylové (BDA) a tetrakyanoquinodimetanu (TCNQ) byly použity efúzní cely. Kvalita a uspořádání vytvořených vrstev byla následně charakterizována nízkoenergiovou elektronovou mikroskopií (LEEM). V práci jsou diskutovány naměřené výsledky a chování molekul na povrchu krystalu po depozici. Difrakční obrazce byly použity pro vytvoření modelu uspořádání molekul v reálném prostoru.
|
|
|
Novel materials for organic and hybrid electronics and photonics
Kratochvíl, Matouš ; Yumusak,, Cigdem (oponent) ; Táborský, Petr (oponent) ; Weiter, Martin (vedoucí práce)
The field of organic electronics offers the unique possibility of mass production of cheap and environmentally friendly electronics. It opens doors to novel functionalities and device forms not possible with the standard metal- and silicon-based electronics. The possibilities given by the nature of organic compounds and progress in synthetic research supply new materials for photonic applications. The search for novel materials and the investigation of the relationship between the molecular (and crystalline) structure and properties of the material are the main motivation of this thesis. This thesis is focused on study of optical and/or electrical properties of novel materials for photonic applications. The materials presented in the thesis are both organic and hybrid organic-inorganic ones, trying to get the best of both worlds. The research presented in this thesis comprises three distinct parts interconnected by the aim to study the relationship between the structure of material and its properties and by the methods used to study these properties. The first part aims to present efficient solid-state fluorescent (SSF) materials. In this thesis two series of SSF materials are presented. The colour of the emission is controlled by varying the electron withdrawing groups in the push-pull systems of molecules. The results show efficient emission (>10 %) covering most of the visible spectrum (~450–650 nm). The second part of the research investigates the effect of thionation on the well-known small-molecule group of semiconductors, diketopyrrolopyrroles (DPPs). The presented result shows a notable preference for n-type behaviour upon thionation with increase of electron mobilities by orders of magnitude, as well as impressively low lying LUMO levels (~ 4,5 eV) in the studied molecules. The third part of the presented results aims at perovskite materials for photonic applications. The hybrid material, organo-lead-halide perovskite, has been the center of attention of researchers interested in advanced photonics for almost a decade and half. The perovskite solar cells have shown remarkable efficiency, however, their utilization is still hindered by stability issues. A stability study is presented as a reference point for further research on this topic and to gather insight into processes influencing the stability of perovskite material and solar cells. Then an approach to increase the stability and performance of the cell is proposed and tested utilizing materials studied in the second study.
|
|
|
Studium elektrických a fotoelektrických jevů v organických polovodičích
Chomutová, Radka ; Toušek, Jiří (vedoucí práce) ; Pfleger, Jiří (oponent)
Práca rozoberá elektrické vlastnosti polymérnych vrstiev polyanilínu, polythiofénov a poly(((benzothiadiazol)4,7-di(thien-2-yl)-5,6-difluoro-2,1,3- benzothiadiazol). Cieľom práce je skúmať ich elektrické a fotoelektrické vlastnosti, ako je elektrická vodivosť, pohyblivosť nosičov náboja, výstupná práca elektrónov a difúzna dĺžka excitónov. Elektrická vodivosť bola meraná s využitím prúdových a napäťových kontaktov, pohyblivosť metódou CELIV (odsávanie náboja lineárne rastúcim elektrickým napätím). Pre merania výstupnej práce bola použitá Kelvinova sonda vlastnej konštrukcie. Difúzna dĺžka excitónov bola určovaná vyhodnocovaním spektier fotonapätia vzniknutého osvietením oblasti priestorového náboja pri povrchu organického polovodiča. Povrchová bariéra vznikla buď spontánne alebo po nanesení usmerňujúcej elektródy.
|
|
|
Synthesis of advanced adamantane containing intermediates based on para-bis (2-thienyl) phenylene. Influence of intramolecular hydrogen bonds on photoisomerization
Veselý, Dominik ; Pospíšilík, Karel (oponent) ; Krajčovič, Jozef (vedoucí práce)
This diploma thesis describes study and onward synthesis of advanced organic structures with potential application in the field of organic electronics and, in particular, molecular photoswitches. In the theoretical part of the thesis are closely described most commonly used conventional molecular photoswitches with special attention to the influence of the structural modifications on properties and applications of the given derivatives. Next passage is dedicated to study of donor-acceptor systems, as fundamental building blocks for synthesis of advanced derivatives. The possibilities of derivatization with a goal of improving the physicochemical properties of these compounds are also discussed. In the final chapter are proposed modern synthetic methods for preparation of novel materials for organic electronics. This section is connected with an experimental part, where are designed and consequently synthesised 4 novel imine derivatives with dodecyl and adamantyl-ethyl side chain.
|
|
|
Organic materials for organic field-effect transistors and electrochemical transistors
Stříteský, Stanislav ; Weis,, Martin (oponent) ; Boušek, Jaroslav (oponent) ; Weiter, Martin (vedoucí práce)
This work is aimed to the study of the properties of organic semiconducting materials with a focus on their conductivity and mobility of charge carriers. The main goal of this thesis is to elucidate the relationship between the chemical structure of organic semiconductors and their properties. The theoretical part of this work is focused on the basics of organic semiconductors, charge transport and a review of the properties of organic semiconducting materials which have led to their application in field-effect and electrochemical transistors. The experimental part presents the overview of the materials used, the methods for their preparation and characterization methods. Within the result part, several methods for thin-film preparation were developed or optimize and subsequently their effect on the performance of organic field-effect transistors were studied. The relevant properties of novel organic semiconducting materials were characterized and discussed with focus on the charge carrier mobility. The biocompatibility of several organic semiconductors were characterized and discussed. Electrical properties, stability and biocompatibility of electroactive polymer inks based on PEDOT:PSS was characterized and discussed with respect to their possible application in bioelectronics. Finally, the organic bioelectronic sensor for detection of the physiological response of cardiomyocytes based on studied materials were constructed.
|
|
|
Low Energy Thermoelectric Generators
Znbill, Laila
The paper describes the possibilities of energy harvesting using thermoelectric generators. It is shown that organic semiconductors enable a large variability of properties and some of their properties may be better than by inorganic semiconductor materials. Nevertheless they suffer from poor electrical conductivity. Because the voltage of one junction is quite low even in case of large temperature difference thermoelectric generators need integration of large number of individual thermo-junctions. Printing technologies enhance effective production of integrated thermo-generators with individual junctions connected in series.
|
|
|
Organic materials for molecular electronics and photonics
Vrchotová, Jana ; Cimrová, Věra (oponent) ; Zmeškal, Oldřich (oponent) ; Weiter, Martin (vedoucí práce)
Organic electronics is a dynamic rapidly growing industry. Therefore the research of novel materials for organic electronics is an important challenge both in terms of materials performance and economy of the final product, while the environmental impact is also important. Diketopyrrolopyrrole derivatives are materials with a great potential for organic electronics exploitation. This thesis is focused on optical and electrical characterization of diketopyrrolopyrroles, an assessment of their potential applications in organic electronics and suggestions, how to optimize their performance. Theoretical part of this thesis describes state of art in organic electronics with focus on the field of diketopyrrolopyrrole based materials. Subsequent results part summarizes important results and contains brief introduction to the enclosed publications, including evaluation of author´s personal contribution to particular publications. Results part consists of 6 scientific articles, integral to this thesis, thematically connected with area of organic electronics, new diketopyrrolopyrrole based materials and their applications. Formally the thesis is, based on article 42 paragraph 1b of The Study and Examination Rules of BUT, designed as thematically arranged set of published works and works accepted for publication.
|
host ::
RSS.