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Zinc(II) phthalocyanines immobilized in mesoporous silica Al-MCM-41 and their applications in photocatalytic degradation of pesticides

Silva, M.; Calvete, M. J. F.; Gonçalves, N. P. F.; Burrows, H. D.; Sarakha, M.; Fernandes, A.; Ribeiro, M. F.; Azenha, M. E; Pereira, M. M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
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In the present study the authors investigated a set of three new zinc(II) phthalocyanines (zinc(II) tetranitrophthalocyanine (ZnTNPc), zinc(II) tetra(phenyloxy)phthalocyanine (ZnTPhOPc) and the tetraiodide salt of zinc(II)tetra(N,N,N-trimethylaminoethyloxy) phthalocyaninate (ZnTTMAEOPcI)) immobilized into Al-MCM-41 prepared via ship-in-a-bottle methodology. The samples were fully characterized by diffuse reflectance-UV–vis spectroscopy (DRS-UV–vis), luminescence, thermogravimetric analysis (TG/DSC), N2 adsorption techniques and elemental analysis. A comparative study was made on the photocatalytic performance upon irradiation within the wavelength range 320–460 nm of these three systems in the degradation of pesticides fenamiphos and pentachlorophenol. ZnTNPc@Al-MCM-41 and ZnTTMAEOPcI@Al-MCM-41 were found to be the most active systems, with the best performance observed with the immobilized cationic phthalocyanine, ZnTTMAEOPcI@Al-MCM-41. This system showed high activity even after three photocatalytic cycles. LC–MS product characterization and mechanistic studies indicate that singlet oxygen (1O2), produced by excitation of these immobilized photosensitizers, is a key intermediate in the photocatalytic degradation of both pesticides.

Synthesis of Phthalocyanines-ALA Conjugates: Water-Soluble Compounds with Low Aggregation

OLIVEIRA, Kleber T. de; ASSIS, Francisco F. de; RIBEIRO, Anderson O.; NERI, Claudio R.; FERNANDES, Adjaci U.; BAPTISTA, Mauricio S.; LOPES, Norberto P.; SERRA, Osvaldo A.; IAMAMOTO, Yassuko
Fonte: AMER CHEMICAL SOC Publicador: AMER CHEMICAL SOC
Tipo: Artigo de Revista Científica
ENG
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Syntheses of two water-soluble phthalocyanines (Pc) containing 5-aminolevulinic acid (ALA) linked to the core structure are described. These compounds were prepared by using original functionalizations, and they present remarkable structural and photophysical features, indicating that they could be applied to photodynamic therapy (PDT).

Preparação e caracterização de sensores de amônia baseados em filmes ultrafinos de polianilina e polianilina-ftalocianinas.; Preparation and characterization of ammonia sensor based on polyaniline and polyaniline-phthalocyanines thin films.

Heleno, Cassia Massucato Nishijima
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 01/11/2007 PT
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O presente trabalho tem como objetivo o estudo e o desenvolvimento de dispositivos eletrônicos, para o monitoramento de gás de amônia, confeccionados com filmes ultrafinos de polianilina e ftalocianinas metálicas. Foram fabricados três diferentes tipos de sistemas: polianilina/PVS, polianilina/ftalocianina de níquel e polianilina/ftalocianina de cobre, sendo a espessura dos filmes o parâmetro de análise. Foram preparadas amostras com 10, 20 e 40 bicamadas. Os filmes foram caracterizados por profilometria e espectroscopia de absorção na faixa da radiação do UV - visível. Observou-se um aumento linear da espessura dos filmes com o aumento do número de bicamadas depositadas. Os dispositivos foram preparados a partir da deposição dos filmes ultrafinos de polianilina e ftalocianinas sobre substratos de vidro com eletrodos interdigitados de ouro evaporados termicamente. Os dispositivos foram caracterizados eletricamente por medidas de variação da resistência elétrica, em regime de corrente contínua e alternada, para diferentes concentrações de amônia. Também foi analisado o efeito da temperatura e da umidade relativa do ar na sensibilidade dos dispositivos. Todas as estruturas apresentaram uma dependência direta do valor da resistência elétrica com a concentração de amônia. Os dispositivos baseados em filmes de polianilina e ftalocianina de níquel apresentaram a menor variação do valor de resistência elétrica com a umidade relativa do ar. Esta característica é bastante desejável já que os ambientes nos quais se pretende utilizar este tipo de dispositivo para de monitoramento do gás de amônia...

Imobilização de ftalocianinas metaladas em hidróxidos duplos lamelares: preparação, caracterização e atividade catalítica; Immobilization of metallated phthalocyanines into layered double hydroxides: preparation, characterization and catalytic activity

Barbosa, César Augusto Sales
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 11/03/2004 PT
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O presente trabalho trata da preparação e da caracterização de sistemas contendo tetrassulfoftalocianinas de Co(II) (CoPcTs) e Fe(III) (FePcTs) intercaladas ou somente adsorvidas externamente em matrizes de hidróxidos duplos lamelares (HDLs). Foram sintetizados materiais com composições variadas e empregando-se diferentes métodos de síntese visando, principalmente, o isolamento de materiais com microporosidade intracristalina e/ou com um baixo grau de agregação da ftalocianina. Técnicas de caracterização textural (difração de raios-X e medidas de área superficial) e espectroscópicas (vibracional na região do infravermelho, eletrônica no UV/visível, ressonância paramagnética eletrônica e absorção de raios-X), além das análises elementar (C, H, N e metais) e termogravimétrica foram utilizadas para a caracterização dos sólidos sintetizados. Avaliaram-se os materiais como catalisadores na reação de oxidação do 2,6-di-terc-butilfenol e do catecol, utilizando O2ou H2O2 como oxidantes. Nos materiais isolados contendo a CoPcTs intercalada em HDLs com composição MgxAl (x = 2, 3 e 4) e ZnxAl (x = 4 e 5), a ftalocianina está orientada perpendicularmente às lamelas do HDL, independentemente do método de síntese e da composição dos HDLs utilizados. Adicionalmente...

Síntese, caracterização e estudo de propriedades de ftalocianinas metálicas na forma de filmes de Langmuir e Langmuir-Blodgett; Synthesis, characterization and properties of metallic phthalocyanines in Langmuir and Langmuir-Blodgett films

Gaffo, Luciana
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/02/2002 PT
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Este trabalho apresenta um estudo sobre síntese, caracterização e propriedades de ftalocianinas metálicas na forma de filmes ultrafinos. Foi obtida mais de uma fração para cada ftalocianina. Para as ftalocianinas de paládio (PdPc) e de ródio (RhPc), apenas uma fração pôde ser totalmente purificada para trabalhos com a técnica Langmuir-Blodgett (LB). As frações de ftalocianina de rutênio (RuPc) não atingiram pureza suficiente para fabricação de filmes de Langmuir e LB. As propriedades das ftalocianinas de ródio e bisftalocianina de itérbio (YbPc2), sintetizada em trabalho anterior, foram estudadas na formação de filmes LB. Observou-se forte influência das condições exterimentais nos resultados. Para a YbPc2, a posição do sensor de medida de pressão altera a pressão de colapso dos filmes, algo que só é observado em filmes de compostos semi-anfifilicos. O potencial de superficie dos filmes de Langmuir depende da velocidade de compressão, mas tais diferenças não aparecem nos filmes LB depositados. Foi observada uma forte interação química entre a RhPc e o ácido esteárico, o que é atípico para ftalocianinas. Esta interação parece ser bem menos intensa nos filmes LB. As áreas ocupadas por molécula para as bisftalocianinas de itérbio e samário e a ftalocianina de ródio foram 69...

Electroactive LbL films of metallic phthalocyanines and poly(O-methoxyaniline) for sensing

Santos, Amanda C.; Zucolotto, Valtencir; Constantino, Carlos J. L.; Cunha, Helder N.; dos Santos, Jos R.; Eiras, Carla
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica Formato: 1505-1510
ENG
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Multilayered nanostructured films have been widely investigated for electrochemical applications as modified electrodes, including the layer-by-layer (LbL) films where properties such as thickness and film architecture can be controlled at the molecular level. In this study, we investigate the electrochemical features of LbL films of poly (o-methoxyaniline; POMA) and tetrasulfonated phthalocyanines containing nickel (NiTsPc) or copper (CuTsPc). The films displayed well-defined electroactivity, with redox pairs at 156 and 347 mV vs SCE, characteristic of POMA, which allowed their use as modified electrodes for detecting dopamine and ascorbic acid at concentrations as low as 10(-5) M.

Nanoscale processing of polyaniline and phthalocyanines for sensing applications

Zucolotto, V; Ferreira, M.; Cordeiro, M. R.; Constantino, CJL; Moreira, W. C.; Oliveira, O. N.
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 809-815
ENG
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Nanostructured polyaniline-modified electrodes were fabricated via the electrostatic layer-by-layer (LbL) technique where polyaniline (PANI) was assembled with one of three tetrasulfonated metallic phthalocyanines, viz. iron (FeTsPc), nickel (NiTsPc) and copper (CuTsPc). The multilayer formation was monitored via UV-vis spectroscopy by measuring the increase in the 800 run absorption band due to PANI. Infrared spectroscopy in the transmission mode suggested specific interactions between PANI and the phthalocyanines, such as those between SO3- groups from the phthalocyanines and the protonated NH group from PANI. The films were employed to detect dopamine (DA) using cyclic voltammetry. In the presence of dopamine the PANI-based LbL films showed additional redox peaks at ca. 230 and 190 mV the oxidation peak increased linearly with the concentration of DA in the electrolytic solution. Films comprising PANI/FeTsPc were able to distinguish between DA and ascorbic acid (AA), which acts as a natural interferent in biological fluids. (c) 2005 Elsevier B.V. All rights reserved.

Tailoring nanostructures of tetraphenyl porphyrins and phthalocyanines on metallic surfaces= : Construção de nanoestruturas de tetrafenil porfirinas e ftalocianinas em superfícies metálicas; Construção de nanoestruturas de tetrafenil porfirinas e ftalocianinas em superfícies metálicas

Shadi Passam Fatayer
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 18/08/2014 PT
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O estudo de sistemas moleculares em cima de substratos metálicos tem atraído uma crescente atenção da comunidade científica. O melhor entendimento sobre as características de auto-organização e a habilidade de controlá-las em moléculas tem gerado formas mais baratas e rápidas de usar a abordagem bottom-up em nanociência. Dentre os diversos estudos feitos, podemos citar o desenvolvimento de sensores de gás que utilizam do sinal magnético de uma camada auto-organizada de moléculas e da ligação de pequenas moléculas como CO ou NO que promovem a emergência de magnetismo na amostra. Outro aspecto interessante do estudo de sistemas moleculares se encontra na similariedade das moléculas que podem ser utilizadas com moléculas encontradas nos processos recorrentes na natureza, por exemplo, as clorofilas e hemoglobinas. Isto significa que ao estudar moléculas simples é possível mimetizar um comportamento parecido com o das moléculas citadas. Neste sentido, em nosso trabalho estudamos dois tipos de moléculas ¿ Porfirinas e Ftalocianinas ¿ e as propriedades estruturais quando depositadas em diferentes substratos metálicos. As porfirinas foram analisadas em uma superfície de baixo índice de Miller, Cu(111), e tiveram seu comportamento comparado com o análogo em superfícies vicinais...

Phthalocyanines : interaction with carbon structures and as PDT agents; Ftalocianinas : interação com estruturas de carbono e como agentes em PDT

Lourenço, Leandro Miguel de Oliveira
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Tese de Doutorado
ENG
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This dissertation describes the synthesis and characterization of different phthalocyanine (Pc) derivatives, as well as some porphyrins (Pors), for supramolecular interaction with different carbon nanostructures, to evaluate their potential application in electronic nanodevices. Likewise, it is also reported the preparation and biological evaluation of interesting phthalocyanine conjugates for cancer photodynamic therapy (PDT) and microorganisms photodynamic inactivation (PDI). The phthalonitrile precursors were prepared from commercial phthalonitriles by nucleophilic substitution of -NO2, -Cl, or -F groups, present in the phthalonitrile core, by thiol or pyridyl units. After the synthesis of these phthalonitriles, the corresponding Pcs were prepared by ciclotetramerization using a metallic salt as template at high temperatures. A second strategy involved the postfunctionalization of hexadecafluorophthalocyaninato zinc(II) through the adequate substituents of mercaptopyridine or cyclodextrin units on the macrocycle periphery. The different compounds were structurally characterized by diverse spectroscopic techniques, namely 1H, 13C and 19F nuclear magnetic resonance spectroscopies (attending the elemental composition of each structure); absorption and emission spectroscopy...

Improved Photodynamic Efficacy of Zn(II) Phthalocyanines via Glycerol Substitution

Chin, Yunni; Lim, Siang Hui; Zorlu, Yunus; Ahsen, Vefa; Kiew, Lik Voon; Chung, Lip Yong; Dumoulin, Fabienne; Lee, Hong Boon
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 19/05/2014 EN
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Phthalocyanines are excellent photosensitizers for photodynamic therapy as they have strong absorbance in the near infra-red region which is most relevant for in vivo activation in deeper tissular regions. However, most phthalocyanines present two major challenges, ie, a strong tendency to aggregate and low water-solubility, limiting their effective usage clinically. In the present study, we evaluated the potential enhancement capability of glycerol substitution on the photodynamic properties of zinc (II) phthalocyanines (ZnPc). Three glycerol substituted ZnPc, 1–3, (tetra peripherally, tetra non-peripherally and mono iodinated tri non-peripherally respectively) were evaluated in terms of their spectroscopic properties, rate of singlet oxygen generation, partition coefficient (log P), intracellular uptake, photo-induced cytotoxicity and vascular occlusion efficiency. Tetrasulfonated ZnPc (ZnPcS4) was included as a reference compound. Here, we showed that 1–3 exhibited 10–100 nm red-shifted absorption peaks with higher molar absorptivity, and at least two-fold greater singlet oxygen generation rates compared to ZnPcS4. Meanwhile, phthalocyanines 1 and 2 showed more hydrophilic log P values than 3 consistent with the number of glycerol attachments but 3 was most readily taken up by cells compared to the rest. Both phthalocyanines 2 and 3 exhibited potent phototoxicity against MCF-7...

Effect of Some Substituents Increasing the Solubility of Zn(II) and Al(III) Phthalocyanines on Their Photophysical Properties

Chernonosov, A. A.; Ermilov, E. A.; Röder, B.; Solovyova, L. I.; Fedorova, O. S.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
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Water solubility of phthalocyanines (Pcs) usually increases by the introduction of charged or carboxy substituents in the peripheral positions of the macrocycle. As a result, such structural changes influence their photophysical and photochemical properties as photosensitizers. Phthalocyanines substituted with four or eight terminal carboxyl groups and having in some cases additional eight positive charges (water soluble phthalocyanines) were studied in order to evaluate the spectroscopic and photophysical effects of these side residues on the chromophore properties. The quantum yield of singlet oxygen (1O2) generation, the triplet-triplet absorption, and the transient absorption spectra were measured and linked to the structure of the substituents. It was shown that charged substituents did not change the quantum yields of 1O2 generation but decrease its lifetimes. The introduction of the charged substituents not only increases the water solubility but also significantly changes absorption, fluorescence, and transient absorption spectra of water soluble Pcs.

Neue Phthalocyanine des Titans : Synthese, Charakterisierung und Nichtlinear Optische Eigenschaften; New Titanium-Phthalocyanines : Synthesis, Characterization and Nonlinear Optical Properties

Barthel, Markus
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
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Die vorliegende Arbeit mit dem Titel „Neue Phthalocyanine des Titans: Synthese, Charakterisierung und Nichtlinear-Optische Eigenschaften“ erläutert die Grundlagen der Phthalocyaninchemie im allgemeinen. Speziell werden die Synthesemethoden sowie die verschiedenen physikalischen und strukturellen Eigenschaften bisher dargestellter Titan(IV) Phthalocyanine (PcTi). Im einzelnen wird auf die Kristallstrukturen, die Photoleitfähigkeit und deren optischen Eigenschaften eingegangen. Gesondert wird nochmals auf die Grundlagen der Nichtlinearen Optik eingegangen und an geeigneten Phthalocyaninkomplexen erläutert. Der zweite Teil der Arbeit beschreibt schwerlösliche, axial substituierte TiPc und die analogen, gut löslichen, tetra-tert.-Butyl substituierten TiPc, die ebenfalls verschieden axial substituiert wurden. Als axiale Substituenten wurden verschieden funktionalisierte Brenzkatechinderivate verwendet. Exemplarisch werden die gewählten Synthesewege beschrieben und es wird gehen detailliert auf die Interpretation der aufgenommen Spektren eingegangen. Die dargestellten schwerlöslichen Komplexe wurden außerdem mittels EXAFS Spektroskopie untersucht, um direkte Aussagen über die Molekülgeometrie dieser Verbindungen zu erhalten. Durch das Vorliegen als amorpher Festkörper ist die Strukturaufklärung durch Röntgenspektroskopie nicht möglich. Ausgewählte Komplexe der löslichen...

Synthese und Charakterisierung neuer Phthalocyanine für eine mögliche industrielle Anwendung; Synthesis and characterization of some new phthalocyanines for potential industrial applications; Synthese und Charakterisierung neuer Phthalocyanine für eine mögliche industrielle Anwendung

Moustafa, Tamer Ezzat Youssef
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
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Zusammenfassung: Das Ziel dieser Arbeit war die Synthese und die Charakterisierung sowie das Studium der nichtlinear optischen Eigenschaften der löslichen monomeren und binuclear phthalocyanine 10 und 11 und der trinuclear Verbindung 13 und 20. Eingeschlossen, ist auch die strukturelle Modifikationen der Pc-Systeme mit (2-ethylhexyloxy) als peripheren Substituenten und Indium-acetylacetonate (Inacac) als axialen Liganden Weiterhin werden asymmetrisches Pc-Systeme mit stickstoff Heterocyclisch 15a-c synthesiert. Erhalten werden sollen wirksamer Systeme in Hinsicht auf ihre OL Eigenschaften, durch eine geeignete Kombination mehrerer struktureller Bestandteile. Die OL Eigenschaften von 16, 19 und 20 gemessen bei 532 nm zeigen, dass diese Klasse von Materialien gute Anwendungsmöglichkeiten als praktische OL bieten. Weiterhin wurde erstmals das dimer (F16PcRu)2 23 dargestellt und seine dimer Struktur besonders durch EXAFS Spectroscopy bewiesen.; Abstract: Our objective in this work is the design, synthesis, structural, physical characterization and the study of the nonlinear optical properties of the highly soluble substituted monomer, binuclear 10 & 11 and trinuclear 13 & 20 phthalocyanines and molecular substances related to them. Included are also structural modifications of Pc´s functionalization of the Pc systems with (2-ethylhexyloxy) as peripheral substituents...

Unexpected reactions and novel glycosylations with benzotriazole and nitrophenyl derivatives; Ungewöhnliche Reaktionen und neuartige Glycosylierungen mit Benzotriazol- und Nitrobenzolderivaten

Alvarez Mico, Xavier
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
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1. Glycosyl sulfonates have been somewhat neglected in recent years, despite of their considerable potential in stereoselective glycosylation. For this reason, the generation of glycosyl donors with nonafluorobutanesulfonyl derivatives has been studied. Using the commercially available nonafluorobutane sulfonyl fluoride, it was found that either trehalose or the glycosylated product could be formed depending on the order in which the reagents were added. The use of 1H-benzotriazole for the transfer of the nonafluorobutane sulfonyl group to glucose and the generation of the glycosyl donor was studied. By studying how to cleave the nonafluorobutane sulfonyl group from thebenzotriazole moiety with phenol, the heterocyclic ring was opened between positions N1 and N2, resulting in a new methodology for the formation of azobenzenes. This reaction was exploited in phthalocyanine chemistry in case of benzotriazole-substituted phthalocyanines. The sulphonated benzotriazole ring could also be opened with phosphor ylides, giving new phosphoranylidenes. When mesyl and tosyl benzotriazoles were used, these groups were transferred to phenol giving the corresponding esters. Triflyl benzotriazole gave first the azo compound and then formed ester. When sugars were used as nucleophiles...

Synthesis of new glycosylated zinc phthalocyanines and naphthalocyanines; Synthese neuer glycosylierter Zink Phthalocyanine und Naphthalocyanine

Iqbal, Zafar
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
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Glycosylated phthalocyanines (Pc’s) despite their great potential for the generation of reactive oxygen species (singlet oxygen), are less common in literature. Reactive oxygen species are potent oxidant and are used for the destruction of cancer cells in a therapeutic technique called as photodynamic therapy (PDT). Objective of this work was to synthesize a structural variety of glycosylated zinc(II) phthalocyanines for PDT applications. We chose to prepare phthalocyanines, tetra- and octaglycosylated with different sugar moieties such as glucose, galactose, cellobiose, lactose and maltose. In tetraglycosylated zinc(II) phthalocyanines sugar moieties e.g. glucose, galactose and maltose were linked at 1,8(11),15(18),22(25) positions of the Pc macrocycle through anomeric oxygen or sulphur atoms (pages 55,86). Synthesis of these Pcs started from 3-nitrophthalonitrile, in which NO2 group was substituted with anomerically deprotected sugar moieties through SNAr mechanism. Hence appropriate acetyl protected sugar molecules were reacted with 3-nitrophthalonitrile to furnish 3-glycosylated phthalonitriles in good yields (page 53). Synthesis of acetylated sugar substituted phthalocyanines was accomplished when 3-glycosylated phthalonitriles were reacted with hexamethyledisilazane (HMDS) in DMF contaning trimethylsilyltriflate (TMSOTf) and zinc acetate...

Untersuchung der Orientierung und der Grenzflächen-Eigenschaften verschiedener Phthalocyanine mit Photoemissions- und Röntgenabsorptions-Spektroskopie und der Kelvinschwinger-Methode; Orientation and interface properties of various phthalocyanines investigated by photoemission and x-ray absorption spectroscopy and the Kelvin probe method

Biswas, Indro Shubir
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
Relevância na Pesquisa
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Nach den Erfolgen der Halbleiter-Elektronik in den vergangenen Jahrzehnten steht mit der Entwicklung organischer Halbleiter die nächste größere Umwälzung in Elektronik, Photovoltaik und Beleuchtungstechnik bevor. Phthalocyanine, eine dem Porphyrin strukturverwandte Molekül-Familie mit zentralem (meist Metall-) Atom, haben neben Ihrer ursprünglichen Verwendung als Farbstoff auch äußerst interessante Halbleiter-Eigenschaften. Aufgrund ihrer hohen Stabilität und Variabilität finden sich Phthalocyanine als aktive Materialien in organischen LEDs, Solarzellen und Feldeffekt-Transistoren und stellen ein sehr gutes Modellmolekül für weitere grundlegende Untersuchungen an der gesamten Materialklasse der organischen Halbleiter dar. In dieser Arbeit werden grundlegende Eigenschaften der Grenzflächen zwischen Phthalocyaninen und möglichen Träger- oder Kontakt-Materialien in den genannten Bauteilen mit Oberflächen-empfindlichen Methoden untersucht. In Kapitel 2 werden die hier hauptsächlich verwendeten Analyse-Methoden, Photoemissions-Spektroskopie (XPS und UPS), Röntgenabsorptions-Spektroskopie und die Kelvin-Schwinger-Methode dargestellt und insbesondere die besonderen Aspekte dieser Methoden mit Synchrotron-Strahlung für Phthalocyanine erläutert. In Kapitel 3 wird das Wachstum von Phthalocyanin-Dünnschichten auf Goldsubstraten und oxidischen Oberflächen untersucht. Das Hauptaugenmerk liegt dabei auf der molekularen Orientierung der planaren pi-konjugierten Systeme. Basierend auf den beobachteten Einflüssen verschiedener Substrate und Substituenten am Molekül in verschiedenen Schichtdicken wird abschließend ein Modell für das Auftreten verschiedener molekularer Orientierungen erstellt. Sie sind dabei von dem Wechselspiel zwischen Molekül-Substrat- und intermolekularer Wechselwirkung abhängig. Ist die erste besonders ausgeprägt...

Einflüsse auf die molekulare Orientierung von Phthalocyaninen in dünnen Schichten; Influences on the molecular orientation of phthalocyanines in thin films

Latteyer, Florian
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
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Die hier vorgestellte Arbeit berichtet über polare, unpolare und flüssigkristalline Phthalocyanine und wie sich deren molekulare Orientierung relativ zur Substratoberfläche herstellen, modifizieren und bestimmen lässt. Es werden verschiedene Phthalocyanine, Methoden und Einflussparameter vorgestellt und diskutiert, da durch einfache chemische Änderungen am Grundgerüst neue chemische und physikalische Eigenschaften entstehen. Parameter wie die Natur des Substrates und äußere Einwirkungen wie die Temperatur beeinflussen die Orientierung und machen die Materialien interessant für die Anwendung in organischer Elektronik. Mit Bindungspartnern am Zentralatom entstehen Phthalocyanine mit permanenten Dipolmomenten, während der Austausch von H durch F oder Cl zu neuen Symmetrien oder Wechselwirkungen führen kann. Die Substitution an der Peripherie mit organischen Resten erzeugt dabei flüssigkristalline Eigenschaften. Durch diese Vielfalt können verschiedene Methoden wie Aufdampfen (im elektrischen Feld), dip-coating, spin-coating und doctor-bladecasting zum Einsatz kommen. Durch Aufdampfen können dünne Schichten erzeugt werden, wobei sich liegende Moleküle auf einkristallinen Substraten (Au(100)), unterschiedliche Orientierungen auf polykristallinen Substraten (Ag und Au Folie) sowie ungeordnete Strukturen (SiO2...

Synthesen nichtperipher glykokonjugierter Zink(II)phthalocyanine; Synthesis of non-peripherally glycoconjugated zinc(II) phthalocyanines

Crucius, Göran
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
DE_DE
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Ziel dieser Arbeit war die Synthese neuer glykosylierter und glykokonjugierter Zinkphthalocyanine für eine mögliche Anwendung in der Photodynamischen Therapie. Besonderer Fokus sollte dabei auf nichtperipheren bis- und octazuckersubstituierten Systemen liegen, deren Strukturen und physikalische Eigenschaften bis zu diesem Zeitpunkt unerforscht waren. Der erste Teil dieser Arbeit beschäftigte sich mit der Darstellung von 3,6-bisglykosylierten und 3,6-bisglykokonjugierten Phthalonitrilen. Die Darstellung der Zuckernitrile mit Glukose-, Mannose- und Galaktoseresten erfolgte auf verschiedenen Synthesewegen. In einem ersten Versuch wurde ausgehend von 2,5-Difluorbenzoylchlorid in einer mehrstufigen Synthese das 3,6-Difluorophthalonitril synthetisiert, welches anschließend durch nukleophile aromatische Substitution mit Galaktose zum 3,6-Bis(1,2:3,4-di-O-isopropyliden-alfa-D-galaktopyranos-6-yl)phthalonitril reagierte. 3,6-Bis(1,2:3,4-di-O-isopropyliden-alfa-D-galaktopyranos-6-yl)phthalonitril konnte ebenfalls aus 2,3-Dicyanohydrochinon und acetalgeschützter Galaktose unter Verwendung von DEAD und PPh3 (Mitsunobu-Reaktion) gewonnen werden. Weiterhin konnten 3,6-bisglykosylierte Phthalonitrile durch nukleophile Substitution von Glykosylbromiden mit Hydrochinon synthetisiert werden. Zur Darstellung glykokonjugierter Phthalonitrile wurden die acetalgeschützten Kohlenhydrate Galaktose...

Binuclear Phthalocyanines: synthesis, characterisation and optical limiting properties; Binukleare Phthalocyanine: Synthese, Charakterisierung und Optical Limiting Eigenschaften

Calvete, Mário
Fonte: Universität Tübingen Publicador: Universität Tübingen
Tipo: Dissertation; info:eu-repo/semantics/doctoralThesis
EN
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One objective of this work is the synthesis and full characterization of binuclear metal phthalocyanines 12-15 containing the same metal or different metals e. g. Ni and Cu in the same molecule (14 and 15), as well as to obtain unsymmetrically substituted binuclear PcM's 12 and 14. Compounds 12 and 13 were synthesized with Ni as central metal in both cavities. Copper and nickel where found to be convenient for the purpose, since both have good chelating and stabilizing properties for the formed phthalocyanines. Other accomplished objective is the design of binuclear metal phthalocyanines in order to achieve effective optical limiting materials, namely with In (22) or Ga (23) as central metals, using the same approach as described for the synthesis of Ni/Ni and Ni/Cu binuclear Pc's. Octasubstituted phthalocyanines with electron donating substituents and GaCl and InCl as central moieties for optical limiting purposes are also synthesized, in order to compare with the "state of art" molecule (tBu4)PcInCl. Due to the synthetic difficulties, the last element of this group, namely Thallium (Tl) has not been studied so far, except in one case. For the first time we synthesized an octaalkoxy substituted thallium–Pc–compound...

Enhanced reverse saturable absorption and optical limiting in heavy-atom-substituted phthalocyanines

Perry, Joseph W.; Mansour, Kamjou; Marder, Seth R.; Perry, Kelly J.; Alvarez, Daniel, Jr.; Choong, Ingrid
Fonte: Instituto de Tecnologia da Califórnia Publicador: Instituto de Tecnologia da Califórnia
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em 01/05/1994
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The reverse saturable absorption and the optical-limiting response of metal phthalocyanines can be enhanced by use of the heavy-atom effect. Phthalocyanines containing heavy-metal atoms, such as In, Sn, and Pb, show a nearly factor-of-2 enhancement in the ratio of effective excited-state to ground-state absorption cross sections compared with those containing lighter atoms, such as Al and Si. In an f/8 optical geometry, homogeneous solutions of heavy-metal phthalocyanines, at 30% linear transmission, limit 8-ns 532-nm laser pulses to ≤ 3 µJ the energy for 50% probability of eye damage) for incident energies as high as 800 µJ.