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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Semi-conducteurs organiques [pi]-conjugués pour l'élaboration de dispositifs photovoltaïques hybrides solides à colorant / Organic hole transporting materials for solid state DSSC

Degbia Wangata, Saint-Martial 15 December 2014 (has links)
Ce travail a consisté à élaborer de nouveaux verres moléculaires transporteurs de trou dérivés du carbazole pour remplacer le spiro-OMeTAD (matériau de référence) dans les cellules solaires hybrides à colorant tout solide. Nous avons synthétisé différents dérivés du carbazole 3, 6, 9 substitués, établi leurs principales propriétés physico-chimiques et les avons utilisés en DSSC solide. Nous avons mis en évidence l'intérêt de greffer des groupements bis(4-méthoxyphényl)amines en positions 3, 6 et des aryles en position 9 du carbazole pour obtenir des matériaux performants. Finalement, cette structure type établie a permis de développer un concept innovant de synthèse de dérivés de carbazole ouvrant la voie à l'élaboration d'une large famille de verres moléculaires et permettant la préparation aisée de structures complexes performantes dans les DSSC solide. Nos meilleurs matériaux ont donné, en dispositifs sans optimisation, des performances comparables à celles du spiro-OMeTAD permettant d'entrevoir à terme la préparation de dispositifs à sensibilisateur pérovskite de rendements supérieurs à 15% / The aim ot this work has been to prepare new hole transporting molecular glasses based on carbazole moieties as an alternative to spiro-OMeTAD (standard material) in solid state dye sentitized solar cells (ssDSSC). We have synthesized several 3, 6, 9 substituted carbazole derivatives and have established their physical and chemical properties prior using them in photovoltaic devices. We have demonstrated the interest of grafting functional groups as bis(4-methoxyphenyl)amines on 3, 6 positions and aryl substitutes on the 9 position of carbazole to obtain efficient materials. Finally, this latter chemical structure has been used as a building block to develop an innovative concept of synthesis of carbazole based materials, smoothing the way to easy synthesis of a wide family of efficient molecular glasses for ssDSSC. Our best materials exhibit similar power conversion efficiency compare to the standard spiro-OMeTAD. According to these preliminary results, we expect reaching power conversion efficiencies over 15% with our carbazole based hole transporting materials associated with peroskite sensitizer.
12

Synthesis of benzocarbazoles, indoloquinolines and indolonaphthridines from thermolysis of benzoenynyl ketenimines and carbodiimides

Shi, Chongsheng. January 2001 (has links)
Thesis (Ph. D.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains ix, 82 p. : ill. Includes abstract. Includes bibliographical references (p. 70-80).
13

Synthesis and Photoelectric Properties of Low Bandgap Thiophene Copolymers

Chang, Ke-ming 23 July 2012 (has links)
In the field of organic solar technology, there are two main problems, the stability of materials and the low power efficiency. By analyzing the power efficiency of organic solar cells, we can infer that efficiency of absorption and charge mobility are the key factors to these two problems. In this study, we focus on coupling carbazole with different low bandgap moieties. By using Suzuki Coupling, we synthesized new conjugated polymers with main chain structures of D-A sequence. It turns out that the copolymer can form a strong intramolecular charge transfer (ICT). We¡¦ve successfully synthesized two new low bandgap copolymers with D-A sequence, PCAMDT and PCAMDP. These two copolymers show us excellent thermal stabilities with decomposition temperature of 320¢Jand 355¢J,respectively.According to UV-Vis absorption spectrum, PCAMDT and PCAMDP own bandgaps at 1.85 eV and 2.22eV,respectively. Electrochemical analysis reveals that the HOMO and LUMO level of PCAMDT are found to be -5.69eV and -3.77eV,repectively, while the HOMO and LUMO level of PCAMDP are -5.87eV and -3.75eV. These properties make PCAMDT and PCAMDP advantageous materials while applied as high absorbing layers of organic solar cells.
14

Palladium-catalyzed synthesis of carbazole derivatives and formal total syntheses of several naturally occurring carbazole alkaloids

Scott, Tricia L. January 2001 (has links)
Thesis (Ph. D.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains x, 83 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 75-78).
15

I. The selective catalytic hydrogenation of pyrrole, indole, carbazole, and acridine derivatives II. The Claisen condensation of carbethoxypyrroles /

Coonradt, Harry Lynn, January 1940 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1940. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 85-87, 105).
16

Carbazole-Fluorenone Dyes

Leontyev, Alexey E. 31 July 2009 (has links)
No description available.
17

Carbazole Based Ambipolar Compounds: A Study of Their Intramolecular Charge Transfer Properties

Estrada, Leandro A. 26 October 2010 (has links)
No description available.
18

Transition metal catalysed reactions for the synthesis of heteroaromatic compounds

Pelly, Stephen Christopher 22 December 2008 (has links)
The carbazole and 2-isopropenyl-2,3-dihydrobenzofuran structures are widely found in many naturally occurring compounds. For example, the naturally occurring anti-cancer compound, rebeccamycin, contains an indolocarbazole core. Rotenone, which contains an (R)-2-isopropenyl-2,3-dihydrobenzofuran moiety, is widely used today as an effective naturally occurring pesticide. In the carbazole section of this thesis, the synthesis of the naturally occurring furanocarbazole, furostifoline is described. As key steps in this sequence, a Suzuki coupling reaction is utilised to couple appropriately functionalised indole and furan moieties. After further functional group transformations, a metathesis reaction is employed to construct the carbazole system, leading to furostifoline. The synthesis of the unnatural thio-analogue of furostifoline was similarly conducted and is described. Finally, in a somewhat different approach, the synthesis of the indolocarbazole core is described, utilising a Madelung approach initially to form the bis-indole system, 2,2’-biindolyl. After several functional group transformations, a metathesis reaction was once again successfully employed to form the carbazole system, thereby synthesising di(tert-butyl) indolo[2,3-a]carbazole-11,12-dicarboxylate. In the benzofuran section of this thesis, the successful chiral synthesis of two 2- isopropenyl-2,3-dihydrobenzofuran systems is described. As a precursor to rotenone, the synthesis of (R)-2-isopropenyl-2,3-dihydrobenzofuran-4-ol is described starting from resorcinol. The key step in this synthesis is a stereoselective intramolecular Pd π-allyl mediated cyclisation utilising the R,R’-Trost ligand, thereby forming (R)-2-isopropenyl- 2,3-dihydrobenzofuran-4-ol in excellent yield and enantiomeric excess. The alternative enantiomer, (S)-2-isopropenyl-2,3-dihydrobenzofuran-4-ol, was similarly synthesised. Finally, a similar approach was utilised to synthesise both (S)- and (R)-2-isopropenyl-2,3- dihydrobenzofuran, starting from 2-allyl-phenol, and thereby completing a formal synthesis of the naturally occurring compounds, (S)-fomannoxin and (R)-trematone, respectively.
19

Synthesis and Mechanistic Studies on the Reaction of N-phenylpyridin-2-Amine Palladacycle with Aryltrifluoroboratess to 9-(pryidin-2yl)-9H-carbazole

Li, Ya-Ming 09 August 2010 (has links)
An effiecient stoichiometric amount system has been developed for the synthesis of N-phenylpyridin-2-amine Palladacycle, and then reation with aryl trifluoroborate to 9-(pyridine-2-yl)-9H-carbazoles by C-H bond activation/ C-C bond formation and C-N bond formation. The subsitutent effect of the aryl trifluoroborate with N-phenylpyridin-2-amine Palladacycle intermediate was observed. Mechanistic studies of C-H bond cleavaged, including trapping of reaction intermediates and kinetic isotope effect experiments, are also presented.
20

Funkcines grupes turinčių elektroaktyvių junginių sintezė ir tyrimas / Synthesis and studies of electronically active compounds containing reactive functional groups

Budreckienė, Rūta 19 July 2005 (has links)
Darbo tikslas buvo skyles pernešančių organinių junginių,gebančių efektyviai tinklintis ar fotopolimerizuotis, sintezė.

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