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The synthesis and study of new derivatives of diketopyrrolopyrroles for organic electronics
Cigánek, Martin ; Maier, Lukáš (referee) ; Krajčovič, Jozef (advisor)
This diploma thesis describes organic pigments of diketopyrrolopyrroles (DDPs) possessing properties applicable in attractive and perspective areas of organic electronics and photonics. The modification of the DPP skeleton was performed by nucleophilic substitution by various alkyl chains and 5 series of DPP derivatives were prepared. The regioselectivity of N-alkylation and also the photophysical properties of the prepared derivatives were studied. A key product of this work is the N,N'-ethyladamantyl derivative of DPP, which exhibited ambipolar characteristic with excellent electron mobility of 0.2 cm2 V–1 s–1. Further, the -conjugation of the above-mentioned DPP derivative was extended by 1 and 2 thiophene units at positions 3,6 and the effect of this modification on optical properties of the resulting derivatives was investigated. A new modified N,N'-unsubstituted DPP derivative was also prepared. The last point of this thesis was the study of the incorporation of formyl functional groups into the skeleton of key N,N'-ethyladamantyl DPP derivative.
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Study of dielectrical properties of organic material thin films
Pospíšil, Jan ; Boušek, Jaroslav (referee) ; Mikula, Milan (referee) ; Zmeškal, Oldřich (advisor)
The dissertation is focused on the study of electric and especially dielectric properties of thin film organic materials with their huge potential for optoelectronics and other industrial sectors. The theoretical part deals with the use of organic materials in organic photovoltaic cells, the methods of deposition techniques and characterization. The theoretical knowledge of the dielectric spectroscopy, including methods for determining the physical properties and evaluation of experimental data are also described. The experimental part is devoted to the study of small molecule organic solar cells with bulk heterojunction composed of electron donor molecule of DPP(TBFu)2 and electron acceptor fullerene derivatives, such as PC60BM, PC70BM and TC60BM. The experimental part is divided into two main parts. The first part deals with the study of processes occurring at the interface between the active layer and the contact; the second part is focused on transport processes inside the structure of photovoltaic cells and also contains a study of perovskite solar cells.
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IMPLEMETATION OF POLYCYCLIC SATURATED SYSTEMS IN ADVANCED SMART MOLECULES USABLE IN ORGANIC ELECTRONICS
Jančík, Ján ; Richtár, Jan (referee) ; Krajčovič, Jozef (advisor)
This essay deals with implementation of polycyclic saturated systems as bulky and very stable molecules, in advanced systems usable in organic electronics. It deals with theoretical aspects of structure and properties of polycyclic saturated systems, which based on available examples and literature are very perspective. Based on theoretical aspect in the first part of essay, the second part deals with synthesis of new molecule with incorporation of polycyclic saturated system usable in organic electronics. This part deals with all main intermediates synthetized via cross-coupling reactions.
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Novel diketopyrrolopyrroles for organic photovoltaics
Hrabal, Michal ; Zmeškal, Oldřich (referee) ; Vala, Martin (advisor)
The aim of this diploma thesis is to conduct optical and photovoltaic characterization of derivatives of diketopyrrolopyrrole (DPP) as materials suitable for fabrication of bulk heterojunction organic solar cells. The charge transfer from donor material (DPP) to acceptor material (PCBM) is studied by a quenching of fluorescence. The photovoltaic response is studied by current – voltage characteristic which can tell us crucial parameters such as shor circuit current density Jsc, open circuit voltage Voc, fill factor FF and power conversion efficiency PCE. Optical characterization was carried out for symmetrical DPP derivatives (U69 and U97) which both contained diphenylaminstilbene moiety and differed in N-alkyl group. On the other hand photovoltaic characterization was conducted for analogous but asymmetrical materials (U70 and U99). Material U29 was characterized as well but its properties proved to be very poor. Both these characterizations tell us that materials with shorter solubilization groups (U69 and U99) are more suitable candidates. Achieved PCE for U70 was 0,74 % and for U99 up to 1,39 %. From these values one can say that small molecule organic materials can be used for fabrication of solar cells.
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Low-molecular materials for organic electronics and photonics
Češka, Matěj ; Salyk, Ota (referee) ; Weiter, Martin (advisor)
This master´s thesis deals with organic materials for use in electronics and photonics. Attention was paid to low molecular weight materials. The theoretical part of this thesis contains brief introduction to organic electronics and photonics. In particular, organic transistors, organic solar cells and organic light-emitting diodes are mentioned. The experimental part is focused on study of electrical and optical properties of two types of phthalocyanines. Thin films and solutions of phthalocyanines were characterized by UV-VIS spectroscopy. Thin films were also characterized by current voltage characteristics, spectral response measurement of photocurrent and by method of transient photoconductivity. It was found that illumination affects the electrical properties of thin layers of phthalocyanines, the performance of the prepared thin films depends on the type phthalocyanine and also depends on the thickness of the layer.
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Utilization of nanomaterials for organic electronic and photovoltaics
Flimel, Karol ; Žídek, Jan (referee) ; Weiter, Martin (advisor)
The study of the new materials potentially usable for organic photovoltaic and electronics are getting very important from the point of ecological and financial view. Organic electronic devices are getting more and more popular and it is only up to us to search for the new ones that are able to improve their physical properties. The aim of this thesis is to search for materials like have been mentioned above which have very good semiconducting properties. Solutions of pure materials and its mixtures with different concentrations of fullerene have been investigated by ultra-violet spectroscopy, classical fluorescence and time resolved spectrometry. Mainly, were studied the influence of the central atom and side substituents for the optical and electronical properties of our materials of interest. With adding fullerene was observed quenching phenomena of the fluorescence, because all these new materials show usually high photoluminescence. Based on the given results, the most suitable materials had been chosen to provide trial of making organic solar cell, and therefore investigated by the mean of electric measurements (direct current).
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Preparation of organic electrochemical tranzistors for biosensorics
Ehlich, Jiří ; Vala, Martin (referee) ; Salyk, Ota (advisor)
The goal of this thesis is to describe the process used in preparation of organic electrochemical transistors thus biosensors for testing potential drugs aimed for cardiomyocytes. Then explore some physical properties of developed sensors such as adhesion of materials used, conductivity of developed structures and stability of developed structures in various water environments. As primary technology used for creating our OECTs was used inkjet printing of special inks with electrical properties on PET and PEN substrate cured with special treatment before and after printing. This thesis results in complete view on technology and development of biosensors we had created.
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Synthesis and studies of novel difuranone heterocycles for optoelectronic applications
Szotkowski, Martin ; Ing. Jan Vyňuchal, Ph.D (referee) ; Krajčovič, Jozef (advisor)
Organic electronics is a progressive field of science that combines knowledge of many disciplines concerned with the study and application possibilities of organic molecules from both, the low-molecular segment as well as the oligomers and polymers. Such molecules are well recognizable by their excellent properties and variability of their structure. This thesis deals with properties, applications and brief research review of benzodifuranones and diketopyrrolopyrroles as the representatives of smart molecules. Furthermore various synthetic approaches to the preparation of both symmetrical and unsymmetrical benzodifuranones are described. Experimental part is focused on the development of hydroxy(thiophene-2-yl) acetic acid initial intermediate for the development of benzodifuranone analogues containing aromatic thiophene core.
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Preparation and study of the reactivity of a new series of N, N'-substituted diketopyrrolopyrrole (DPP) for organic photonics
Cigánek, Martin ; Vyňuchal, Jan (referee) ; Krajčovič, Jozef (advisor)
Currently, the major trend is the development of materials that could be used for transformation of solar energy into electrical energy. Organic photovoltaics studies this area of interest and especially in recent years increasingly tries to put functional materials of organic origin into practice. These materials belong to a group of "high performance pigments" due to their exceptional and relatively stable properties. One of the most important molecules are the diketopyrrolopyrroles (DPP) derivatives. The theoretical part of this bachelor work describes the organic electronics and photonics, DPP derivatives, various synthetic routes of DPP, properties of particular DPP derivatives and the dependence of their properties on the used substituents. There are described separation and analytical methods most commonly used in organic synthesis too. The experimental part describes the preparation of the backbone DPP containing thiophene units. The following are the modifications of DPP backbones with N,N‘-alkylation and N,N‘-arylation.
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