National Repository of Grey Literature 24 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
The synthesis and functionalization of diketopyrrolopyrrole derivatives for organic electronics
Mamleev, Kamil ; Halaksa, Roman (referee) ; Krajčovič, Jozef (advisor)
Nowadays, organic electronics is a promising field of science. Because of a number of advantages, materials based on organic substances can replace existing inorganic analogues in such devices as organic solar cells, OLED, OFET, biosensors, etc. In the theoretical part of the bachelor's thesis, the molecules of diketopyrrolopyrrole (DPP), dithioketopyrrolopyrrole (DTPP), and their derivatives were fully reviewed. An overview of the synthesis and the properties of the derivatives of these molecules was given. Possible applications of DPP and DTPP in various areas of organic electronics were provided. The experimental part of the bachelor's thesis described the synthesis of DTPP structures with thiophene and phenyl substituents. In addition, a modification of thiophene DTPP with S'S alkylation was demonstrated. All synthesized compounds were purified by silica gel column chromatography. The structures of the obtained products were characterized by 1H NMR spectroscopy.
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.
Preparation of diketopyrrolopyrrole-based (DPP) polymers for organic electronics
Solanský, Lukáš ; Veselý, Dominik (referee) ; Cigánek, Martin (advisor)
The modern world is burdened by dependence on electricity and problems with its production. A very advantageous way to gain electricity is through photovoltaics. However, the production of silicon solar cells is demanding and expensive with a high impact on the environment. For this reason, there is an effort to switch to solar cells based on organic semiconductors. These include, for example, polymers based on diketopyrrolopyrrole (DPP). The theoretical part of this thesis deals with organic electronics, conductive polymers and DPP-based polymers, their properties and applications. It further describes the most common synthetic approaches to DPP-based polymers. The experimental part of this final work describes the preparation of intermediates necessary for the synthesis of the resulting DPP-based polymers using Stille reaction. The thiophene derivative of DPP was N,N'­alkylated and subsequently brominated. Furthermore, organotin intermediates were prepared, which together with the dibrominated DPP derivative participate in the polymerization.
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.
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.
Modification of Organic High Performance Pigments for Applications in Organic Electronics
Cigánek, Martin ; Imramovský, Aleš (referee) ; Vyňuchal, Jan (referee) ; Krajčovič, Jozef (advisor)
Dizertační práce pojednává o studiu, syntéze a chemické derivatizaci molekul spadajících do skupiny organických vysoce výkonných pigmentů a jejich potenciálním uplatnění v oblastech organické elektroniky. Teoretická část práce je zaměřena na nejnovější trendy v dané oblasti, a to jak z aplikačního potenciálu konkrétních derivátů, tak z pohledu syntetických možností a jejich strukturálních derivatizací. V experimentální části je pak podrobně popsána příprava pestré škály intermediátů a výsledných produktů, zahrnujících deriváty diketopyrrolopyrrolů (DPP), benzodifuranonu (BDF), epindolidionu (EP), naphthyridinedionu (NTD) a polymeru na bázi thiofenu (PT). Celkově bylo nasyntetizováno 103 molekul, přičemž 49 tvořily výsledné produkty, z nichž 27 bylo zcela nových, dosud nepublikovaných. Hlavním motivem derivatizace molekul pigmentů je zde inkorporace derivátů adamantanu do finálních struktur. V další části práce jsou blíže diskutovány jednotlivé chemické modifikace vedoucí k výsledným produktům. Na sérii N,N'-; N,O'- a O,O'-substituovaných derivátů DPP je popsána komplexní studie vlivu charakteru alkylových řetězců a také pozice jejich navázání v molekule DPP, a to nejen na selektivitu reakce, ale rovněž na optické i termické vlastnosti syntetizovaných produktů.
Testing of hydrogen sensor based on organic materials
Petrová, Lenka ; Hubálek, Jaromír (referee) ; Boušek, Jaroslav (advisor)
Práce je zaměřena na problematiku bezpečnostních vodíkových senzorů. Základní principy a teorie vodíkových senzorů je rozebrána v první části práce. Je navržena metodologie testování organických vodíkových senzorů vyvinutých a vyrobených na Fakultě Chemické Vysokého Učení Technického v Brně. Nejslibnější organický material byl testován. V závěrečné části byl navržen teplotní regulátor pro použití s keramickou senzorovou platformou.
Design and characterization of organic semiconductor components
Juračka, Martin ; Hubálek, Jaromír (referee) ; Sedláček, Jiří (advisor)
The theoretical part of this work gives a summary of the history of the development of organic TFT transistors, explains the basic physical events in the organic semiconductors and analyzes the most widely used materials for OTFT. The practical part of this work deals with a design of the organic components and finally, their characteristics.
Study of sensoric properties of organic semiconductors
Saska, Pavel ; Šedina, Martin (referee) ; Salyk, Ota (advisor)
Compounds based on diketopyrrolopyrrole are organic pigments that behave as semi-conductors. Their analogues with pyridyl side group are due to their sensitivity to hydrogen potentially useful as hydrogen sensors. The aim of this work was to examine properties of sensors with an active layer of diketopyrollopyrolle derivatives. The sensors were tested on an apparatus built for this purpose at FCH VUT in Brno. More specifically, changes to conductivity of these sensors in the presence of hydrogen under various conditions were studied.
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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