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1
Qin, Peng. "The study of organic dyes for p-type dye-sensitized solar cells." Doctoral thesis, KTH, Organisk kemi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-24406.
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This thesis concerns the study of D–π–A type dyes as sensitizers for NiO-based p-type dye-sensitized solar cells. The focus has been on the design and synthesis of efficient dyes and the identification of parameters limiting the solar cell performance. We have developed a new design strategy for the dyes: upon photoexcitation of the dye, the electron density is moving from the part that is attached to the semiconductor towards the part which is pointing away. This intramolecular charge transfer provides an efficient pathway for the following charge transfer processes. The first organic dye, composed of a triphenylamine (TPA) moiety as the electron-donor, dicyanovinyl groups as the electron-acceptors and linked by thiophene units, showed much better photovoltaic performance than other dyes reported at the same time, turning it into a model for future dye design. A series of dyes with different energy levels were synthesized and characterized on NiO-based devices using iodide/triiodide as redox couple. Lower photovoltaic performance was obtained for the dye with less negative reduction potential due to the insufficient driving force for dye regeneration. We have investigated the symmetric and unsymmetric structures of the dyes. The breaking of molecular symmetry did not significantly broaden the absorption spectrum, or improve the efficiency. In addition, we have tuned the molecular structure to prevent charge recombination. Increasing the distance between the anchoring group and the electron-acceptor was an effective way to improve the device efficiency. Besides TPA-based compounds, a zinc porphyrin dye was also synthesized and tested in p-type solar cells. However, the solar cell performed less well due to its narrow absorption band and the tendency for aggregation. Co-sensitization of the TPA-based dye with the porphyrin dye did not result in higher photovoltaic performance. After optimization of the dye structure, the highest overall conversion efficiency was achieved for the P5-sensitized solar cell, based on 1.5 μm NiO film prepared from NiCl2 and the F108 template precursor, and an acetonitrile-based electrolyte.QC 20100909
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Marinado, Tannia. "Photoelectrochemical studies of dye-sensitized solar cells using organic dyes." Doctoral thesis, Stockholm : Skolan för kemivetenskap,Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11248.
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Patel, Dinesh G. "Organic dyes for photoswitching and photovoltaic applications /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/8537.
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Cappel, Ute. "Characterisation of Organic Dyes for Solid State Dye-Sensitized Solar Cells." Doctoral thesis, Uppsala universitet, Fysikalisk kemi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-150047.
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Energy from the sun can be converted to low cost electricity using dye-sensitized solar cells (DSCs). Dye molecules adsorbed to the surface of mesoporous TiO2 absorb light and inject electrons into the semiconductor. They are then regenerated by the reduced redox species from an electrolyte, typically consisting of the iodide/tri-iodide redox couple in an organic solvent. In a solid state version of the DSC, the liquid electrolyte is replaced by an organic hole conductor. Solid state DSCs using 2,2'7,7'-tetrakis-(N,N-di-p-methoxyphenyl-amine)-9,9'-spirobifluorene (spiro-MeOTAD) have reached conversion efficiencies of up to 6 %, which is about half of the efficiency of the best iodide/tri-iodide cells. Measurement techniques, such as spectroelectrochemistry and photo-induced absorption spectroscopy (PIA), were developed and applied to study the working mechanism of organic dyes in solid state DSCs under solar cell operating conditions. The energy alignment of the different solar cell components was studied by spectroelectrochemistry and the results were compared to photoelectron spectroscopy. PIA was used to study the injection and regeneration processes. For the first time, it was shown here that the results of PIA are influenced by an electric field due to the electrons injected into the TiO2. This electric field causes a shift in the absorption spectrum of dye molecules adsorbed to the TiO2 surface due to the Stark effect. Taking the Stark effect into consideration during the data analysis, mechanistic differences between solid state and conventional DSCs were found. A perylene dye, ID176, was only able to efficiently inject electrons into the TiO2 in presence of lithium ions and in absence of a solvent. As a result, the sensitiser worked surprisingly well in solid state DSCs but not in liquid electrolyte ones. Regeneration of oxidised dye molecules by spiro-MeOTAD was found to be fast and efficient and spiro-MeOTAD could even reduce excited dye molecules.
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Swatton, Stewart Nathan Ridgley. "Dynamic excited state properties of organic dyes." Thesis, University of Exeter, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244422.
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LEANDRI, VALENTINA. "Organic materials for dye-sensitized solar cells." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/49809.
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Worrall, David Robert. "Laser photolysis of photographic image dyes." Thesis, Loughborough University, 1992. https://dspace.lboro.ac.uk/2134/25247.
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Studies have been carried out investigating the photochemical and photophysical properties of pyrazolotriazole azomethine dyes. Such compounds can be used as magenta images in the subtractive colour photographic process. This work has been carried out both in dilute fluid solution and in high concentration, high viscosity systems designed to mimic the photographic product. Picosecond pump-probe laser flash photolysis studies have provided the first observation of photoinduced transient absorption changes attributable to the excited states of this class of dyes, and have allowed assignment of the excited singlet state lifetime as being in the range 1 to 3ps at room temperature, with little dependence upon solvent properties or the pattern of substituents on the dye skeleton. Using picosecond laser flash photolysis it has also been possible to observe evolution of the population along the ground state potential surface to the two isomeric forms, the rate of this process showing some solvent dependence. Nanosecond and picosecond laser flash photolysis studies have been used to investigate the process of syn-anti and anti-syn isomerisation about the azomethine linkage. The syn-anti photoisomerisation occurs on picosecond timescales, the anti isomer so produced relaxing thermally back to the syn form on timescales ranging from microseconds to milliseconds. The rate constant for this process is a complex function of solvent properties as well as being dependent upon steric factors within the molecule, and the reasons for this are discussed. Triplet energy sensitisation studies have demonstrated that a pathway exists for this isomerisation process via the triplet manifold, and has allowed determination of minimum isomerisation quantum yields from the triplet state. Such studies have also allowed estimation of limits for the molar decadic absorption coefficients of the anti isomer. The photographic product dyes have been demonstrated to be efficient quenchers of singlet molecular oxygen, the quenching mechanism being predominantly physical in nature. The quantum yields of singlet oxygen production are too small to be measured using time resolved techniques. These factors are used to explain in part the resistance of such compounds to oxidative photodegradation. Steady state irradiation of azomethine dyes in systems designed to simulate the photographic product by a high intensity source of known spectral profile has allowed determination of the quantum yields of photodegradation, which in combination with the results obtained in fluid solution provide a basis for explaining the behaviour of image dyes in the photographic product environment.
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Rogge, Carsten. "Photophysical studies of organic dyes in polymer matrices." Thesis, Cranfield University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266485.
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Bennett, Philip Mark. "Two-photon dyes for biological application." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:b8cb9ce4-35eb-433c-86fc-b5df53a2e566.
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Two photon absorption (TPA) is the near simultaneous absorption of two photons of light to achieve an electronically excited state. It has led to huge advances in microscopy and microfabrication due to its quadratic dependence on the local light intensity. This thesis describes the design, synthesis and application of dyes with strong TPA properties, and as such is divided into three chapters. The first introduces the theory and measurement of TPA as well as structure-property relationships known to maximise the efficiency of TPA. The subsequent chapters present explorations of the application of these dyes in biological applications; namely two-photon uncaging and two-photon photodynamic therapy. A recurring theme in my research is the discussion and evaluation of strategies for improving the compatibility of organic macromolecules with biological systems. Uncaging is the use of photolysis to achieve a rapid increase in the local concentration of a physiologically active species via a photoremovable protecting groups. Photoremovable protecting groups are covalently attached to the physiologically active species, thus rendering it inactive. At the desired time and location, a light dose releases the molecule in its active form. There are many compounds known to uncage following photoexcitation, but there are few examples of caging groups which exhibit both strong two-photon absorption properties and highly efficient uncaging. Chapter 2 discusses the rational design of such groups through the development of a new mechanism for uncaging, in which a photoinduced electron transfer (PeT) between a two-photon-excited electron donor and an electron acceptor/release group drives the uncaging event. Photodynamic therapy (PDT) is a treatment for neoplastic disorders such as cancer in which localised cell death is induced through photoexcitation of a sensitiser. Following light absorption, the photosensitiser enters a relatively long-lived excited state which reacts with cellular oxygen to produce its highly cytotoxic singlet form. The main challenges of the field are to achieve deep penetration of light into tissue and to reduce coincident damage to unaffected tissue by light scattering during irradiation. In 2008, the Anderson group reported the development of PDT photosensitisers with highly efficient two-photon absorption as well as high singlet oxygen quantum yields. Chapter 3 discusses strategies for improving the pharmacokinetics and defining the sub-cellular localisation of these photosensitisers.
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Davies, Richard Andrew. "Theoretical and computational aspects of organic chemistry." Thesis, Bangor University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285502.
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Murray, S. G. "Solution and polymer photochemistry of azo dyes." Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371437.
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Liu, Xiaogang. "Structure-property relationships of organic coumarin-based dyes for use in dye-sensitized solar cells." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708514.
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Koppetsch, Karsten J. "Photodegradation of organic photochromic dyes incorporated in ormosil matrices." Link to electronic thesis, 2000. http://www.wpi.edu/Pubs/ETD/Available/etd-0509100-092225/.
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Shi, Yanrong. "Squaraine dyes for non-linear optics and organic electronics." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/44720.
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This dissertation describes the investigation of the synthesis and characterization of new squaraine-based photonic and electronic materials. In the first part of this thesis, squaraine dyes with large conjugation systems, including extended squaraines consisting of bis(donor)substituted vinylene-heterocycles and bis(indolinylenemethyl)squaraine-based oligomers linking through different π-bridges were designed, synthesized and characterized to exhibit strong two-photon absorption (2PA) for femotosecond and nanosecond optical-power limiting applications in the near-infrared (NIR). One of the dendronized squaraine forms smooth and high optical quality films with large NIR transparency window. In the second part, a series of squaraine- and phthalocyanine-based metal complexes were studied. Those dyes did not show large triplet quantum yield but significantly improved photovoltaic performance compared to the metal-free compounds. In the last part, an effective approach on optimizing bis(indolinylenemethyl)-based squaraine sensitizers with various surface anchor groups and π-linkers, achieved high power conversion efficiencies (PCEs) of 6.7% in liquid dye-sensitized solar cells (DSSCs) and 2.7% in solid-state DSSCs, which stand out all the previous reported squaraine-based sensitizers.
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Alshehri, Maysa. "Photodegradation of organic dyes with nanotitania embedded in hydrogels." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2016. http://digitalcommons.auctr.edu/dissertations/3131.
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The objective of this research was to study the adsorption and photodegradation of Malachite Green (MG) dye by using poly(2-hydroxyethylmethacrylate) (PHEMA) hydrogel and nanocomposite TiO2PHEMA hydrogel. The nanocomposite gels were characterized by FT-IR and XRD. The adsorption of MG dye was examined through monitoring UV-Vis absorption. The kinetic study indicated that the adsorption follows the first order kinetics. The adsorption equilibrium data fit well to the Langmuir isotherm model. The photodegradation of MG dye was examined using TLC UV lamp and medium pressure Hg lamp. It was determined that the unloaded composite gels adsorb MG dye from the solution at the beginning while under the photochemical condition. The dye in the gel was eventually photodegraded, indicating that the photodegradation process is still effective to dyes in the gel system. The composite gels containing anatase/rutile mixed phase titania are much better photocatalysts than those containing pure phase titania (either rutile or anatse).
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Walker, Philip Anthony. "Synthesis of functionalised benzothiophenes and novel heterocyclic dyes." Thesis, Bangor University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278813.
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Gabrielsson, Erik. "Molecular Engineering of D-π-A Dyes for Dye-Sensitized Solar Cells." Doctoral thesis, KTH, Organisk kemi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-144874.
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Dye-sensitized solar cells (DSSCs) present an interesting method for the conversion of sunlight into electricity. Unlike in other photovoltaic technologies, the difficult tasks of light absorption and charge transport are handled by two different materials in DSSCs. At the heart of the DSSC, molecular light absorbers (dyes) are responsible for converting light into current. In this thesis the design, synthesis and properties of new metal-free D-π-A dyes for dye-sensitized solar cells will be explored. The thesis is divided into six parts: Part one offers a general introduction to DSSCs, dye design and device characterization. Part two is an investigation of a series of donor substituted dyes where structural benefits are compared against electronic benefits. In part three a dye assembly consisting of a chromophore tethered to two electronically decoupled donors is described. The assembly, capable of intramolecular regeneration, is found to impede recombination. Part four explores a method for rapidly synthesizing new D-π-A dyes by dividing them into donor, linker and acceptor fragments that can be assembled in two simple steps. The method is applied to synthesize a series of linker varied dyes for cobalt based redox mediators that builds upon the experience from part two. Part five describes the synthesis of a bromoacrylic acid based dye and explores the photoisomerization of a few bromo- and cyanoacrylic acid based dyes. Finally, in part six the experiences from previous chapters are combined in the design and synthesis of a D-π-A dye bearing a new pyridinedicarboxylic acid acceptor and anchoring group.QC 20140509
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Rambacher, Robert William. "Pyridoimudazolium cationic dyes theory, synthesis, and sub-cellular localization /." Huntington, WV : [Marshall University Libraries], 2004. http://www.marshall.edu/etd/descript.asp?ref=163.
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Thesis (M.S.)--Marshall University, 2004.Title from document title page. Includes abstract. Document formatted into pages; contains viii, 79 p. including illustrations. Includes bibliographical references (p. 56).
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Haji, Mohd Yusoff Abdull R. bin. "Cathodic stripping voltammetric studies on sulfonamides and reactive dyes." Thesis, Loughborough University, 1996. https://dspace.lboro.ac.uk/2134/32235.
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Rudolph, Melanie [Verfasser]. "Photoelectrochemical characterization of dye-sensitized solar cells based on ZnO and organic dyes / Melanie Rudolph." Gießen : Universitätsbibliothek, 2016. http://d-nb.info/1104683466/34.
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Hua, Yong. "Design and synthesis of new organic dyes for highly efficient dye-sensitized solar cells (DSSCs)." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/71.
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Dye-sensitized solar cell (DSSC) has attracted increasing interest as a promising hybrid organic-inorganic solar cell. At the heart of the device is a photosensitizer, which is anchored onto a wide-bandgap semiconducting metal oxide. It harvests solar light and transfers the energy via electron transfer to a suitable material (e.g. TiO2) to produce electricityas opposed to chemical energy in plant. The topic of this thesis focuses on the design and synthesis of metal-free organic dyes for applications in DSSCs. Specific attention has been paid to the correlation between the molecular structures and physical properties, as well as their performances in DSSCs. Chapter 1 presents the major components and working principle of DSSC, following by a brief overview of the development of organic dyes and their application in DSSCs. In chapter 2, we have designed two types of new phenothiazine-based dyes to investigate the positioning effect a donor group on the cell performance. The structural features of a donor aryl group at the C(7) position of phenothiazine core extend the π-conjugation of the chromophore and efficiently suppress the dye aggregation on TiO2 film. As a result, Type 1 dyes have better light harvesting properties in contact with TiO2 films, and give much better photovoltaic performance than Type 2 dyes. Chapter 3 presents the synthesis and characterization of a series of simple phenothiazine-based dyes, in which, a linear electron-rich (4-hexyloxy)phenyl group at C(7) of the phenothiazine periphery as the donor, and an alkyl chain with different length at N(10). The dye molecules show a linear shape which is favorable for the formation of a compact dye layer on the TiO2 surface, while their butterfly conformations can sufficiently inhibit molecular aggregation. Moreover, the alkyl substituents with different chain length at N(10) could further optimize the performance through complete shielding the surface of TiO2 from the Iˉ/I3ˉ electrolyte. Under simulated AM 1.5G irradiation, the PT-C6 based DSSC produces a short-circuit photocurrent of 15.32 mAcm−2, an open-circuit photovoltage of 0.78 V, a fill factor of 0.69, corresponding to a power conversion efficiency (PCE) of 8.18%. Moreover, we designed a stepwise approach for co-adsorption of the organic dye PT-C6 with a porphyrin dye (ZnP) for DSSCs. Upon optimization, the device made of the PT-C6 + ZnP system yielded Jsc = 19.36 mA cm-2, Voc =0.735 V, FF = 0.71 and η = 10.10%. In chapter 4, we further developed five organic dyes appended with T, TT, E, ET, or EE (T and E denote thiophene and 3,4-ethylenedioxythiophene (EDOT), respectively) on the C(7) atom of phenothiazine core as electron donors. We have also analyzed the structure-performance corelations of dye molecules in the aspect of dye aggregation, electron injection, dye regeneration and interfacial charge recombination of electrons with electrolytes and/or oxidized dye molecules, through DFT calculation, impedance analysis and transient photovoltage studies. In chapter 5, we extended our studies by using phenothiazine as a building block to construct 3D bulky organic dyes. We systematically investigated the influence of 3D bulky substituents on dye aggregation and charge recombination, as well as photovoltaic performance of DSSCs. The molecular design strategy demonstrates that high Voc can be realized by employing 3D-phenothiazine dyes featuring a bulky substituent, such as, hexylcarbazole and dihexylfluorene units. Impressively, the co-adsorbent-free DSSCs based on dye TP3 exhibits a photovoltaic performance with efficiency up to 8.00 %. In order to realize a panchromatic absorption and further enhance the energy conversion efficiency of DSSCs, we also designed a stepwise approach for co-adsorption of the organic dye TP3 with a NIR dye YR6 for co-sensitized DSSCs. Upon optimization, the device made of the TP3 + YR6 system yielded Jsc = 19.18 mA cm-2, Voc =0.721 V, FF = 0.712 and η = 9.84 %. The power-conversion efficiency is the highest reported efficiency for a squaraine dye-based co-sensitized panchromatic DSSCs. From chapters 6 and 7, a series of new simple panchromatic dyes based on thiadiazolo[3,4-c]pyridine (PyT) have been designed for panchromatic DSSCs. These new organic dyes exhibit broad absorption spectrum in the range of 300~850 nm and high molar extinction coefficients. The electrochemical analyses demonstrate that the incorporation of the auxiliary electron-deficient thiadiazole[3,4-c]pyridine unit can fine-tune the HOMO and LUMO energy levels and red-shift the absorption spectra to NIR region. The overall conversion efficiencies of liquid-electrolyte DSSCs based on these sensitizers range from 0.46 to 6.30 %. We draw some conclusions in chapter 8 together with the outlooks in DSSCs
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Mcclure, Kathryn Raeburn. "Development of new extraction methods for analysis of natural and synthetic organic colourants from historical and artistic matrices." Master's thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/29168.
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Abstract:
In this thesis, an innovative approach for the extraction and clean-up of natural and synthetic
textile dyes based on a recently developed ammonia extraction protocol and a novel
Dispersive Liquid-Liquid Microextraction (DLLME) is presented. The thesis builds upon recent
research highlighting the benefits of the ammonia-based extraction protocol for efficient
extraction and preservation of the glycosyl moieties present in some types of natural dyes.
This state-of-the-art extraction technique requires the use of a clean-up step to purify and preconcentrate the dye molecules for analysis. This clean-up step has never before been
investigated or developed, and current methods rely upon traditional Liquid-Liquid Extractions
(LLE), which are not well suited to the very small quantities of materials available for the
analysis of artefacts of cultural heritage. The novel DLLME protocol presented by this thesis
was developed in order to improve the recovery of natural dyes for analysis, and is also the
first clean-up protocol to be developed for the analysis of synthetic textile dyes from cultural
heritage matrices. Whilst a clean-up system has never before been applied to synthetic dyes
within cultural heritage, pre-concentration and pre-treatment protocols are frequently reported
for analysis of the same type of dyes used in food colourants. For this reason, this research
adapts a DLLME method from the analysis of edible products, and combines this with the
state-of-the-art ammonia extraction method reported in literature. DLLME protocols for both
natural and synthetic dyes were developed and optimised first on known analytical standards,
considered representative of the possible structures of natural dyes and synthetic azoic acid
dyes respectively. The extraction recoveries of a variety of disperser and extraction solvents
were analysed using HPLC coupled with targeted mass spectrometry. The optimised
conditions were then coupled with the ammonia based extraction to ensure coherence of the
methods. The results showed significant improvements in the recovery of natural dye analytes
compared to current methods, as well as increased precision and efficiency. For synthetic
dyes, results showed adequate recovery of analytes and allowed the ammonia-based
extraction method to be applied successfully for the first time. After optimisation, the protocol
for synthetic dyes was applied successfully to 15 samples (11 fibres, 4 powders) of suspected
azo dyes from the Azienda Coloranti Nazionali e Affini (ACNA) synthetic dye collection housed
at Sapienza University of Rome’s Museum of Chemistry. The novel protocol was performed
after preliminary Raman screening to obtain some introductory information about the unknown
samples in the collection. After application of the novel protocol, the samples were identified
through untargeted analysis by HPLC-HRMS.
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Gandolfo, D. S. "The electrical and optical properties of non linear organic dyes." Thesis, Cranfield University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274221.
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El-Zohry, Ahmed M. "Exploring Organic Dyes for Grätzel Cells Using Time-Resolved Spectroscopy." Doctoral thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-263143.
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Grätzel cells or Dye-Sensitized Solar Cells (DSSCs) are considered one of the most promising methods to convert the sun's energy into electricity due to their low cost and simple technology of production. The Grätzel cell is based on a photosensitizer adsorbed on a low band gap semiconductor. The photosensitizer can be a metal complex or an organic dye. Organic dyes can be produced on a large scale resulting in cheaper dyes than complexes based on rare elements. However, the performance of Grätzel cells based on metal-free, organic dyes is not high enough yet. The dye's performance depends primarily on the electron dynamics. The electron dynamics in Grätzel cells includes electron injection, recombination, and regeneration. Different deactivation processes affect the electron dynamics and the cells’ performance. In this thesis, the electron dynamics was explored by various time-resolved spectroscopic techniques, namely time-correlated single photon counting, streak camera, and femtosecond transient absorption. Using these techniques, new deactivation processes for organic dyes used in DSSCs were uncovered. These processes include photoisomerization, and quenching through complexation with the electrolyte. These deactivation processes affect the performance of organic dyes in Grätzel cells, and should be avoided. For instance, the photoisomerization can compete with the electron injection and produce isomers with unknown performance. Photoisomerization as a general phenomenon in DSSC dyes has not been shown before, but is shown to occur in several organic dyes, among them D149, D102, L0 and L0Br. In addition, D149 forms ground state complexes with the standard iodide/triiodide electrolyte, which directly affect the electron dynamics on TiO2. Also, new dyes were designed with the aim of using ferrocene(s) as intramolecular regenerators, and their dynamics was studied by transient absorption. This thesis provides deeper insights into some deactivation processes of organic dyes used in DSSCs. New rules for the design of organic dyes, based on these insights, can further improve the efficiency of DSSCs.
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Calvo-Castro, Jesus. "Engineering diketopyrrolopyrrole organic dyes towards their uses in optoelectronic devices." Thesis, University of the West of Scotland, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.667753.
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Back, Andrew Scott. "Molecular architecture of ordered thin films of crystalline organic dyes." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282491.
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The factors which determine the growth mode and molecular architecture of vacuum deposited organic thin films on single crystalline substrates were investigated. Specifically, the relative importance of layer planes in the bulk structure, lattice matching between the overlayer and substrate, topographic direction by the substrate, and specific molecule-substrate interactions, in determining the growth mode were examined. The majority of the molecules studied here (ClAlPc, F₁₆ZnPc, PTCDA, C4-PTCDI, and C5-PTCDI) exhibited layer planes in their bulk structures, however, the molecular plane is coincident with the layer plane only for PTCDA and ClAlPc. ClAlPc and F₁₆ZnPc were found to adopt different flat-lying commensurate square lattices on the Cu(100) surface. In both cases, the flat-lying orientation of the molecules was dictated by specific molecule-substrate interactions, while the orientation of the lattice was dictated by lattice matching with the substrate. ClAlPc was also able to adopt an incommensurate centered rectangular lattice whose orientation was directed by alignment along step edges. Fluorescence investigation of submonolayer PTCDA and PTCDI films on alkali halide substrates demonstrated the great potential of fluorescence spectroscopy as a means of monitoring film growth. PTCDA was found to adopt a flat-lying orientation on NaCl, KCl, and KBr, while a flat-lying orientation of the PTCDI molecules was determined by the strength of the molecule-substrate interactions. From these measurements, the relative interaction strengths of the substrates were determined to be KCl > KBr > NaCl. IR dichroism showed that the expected growth along the layer planes was found only to occur for PTCDA, due to the coincidence of the layer and molecular planes. IR spectroscopy also revealed that a new polymorph of C5-PTCDI had been formed on these surfaces. These studies showed that the relative importance of the factors in determining the molecular architecture adopted within the first 1-2 MLE of a film are: (1) molecule-substrate interaction, (2) lattice matching, (3) topographic direction, (4) layer planes in the bulk structure. In addition the use of fluorescence spectroscopy to probe the evolution of vacuum deposited films was significantly advanced.
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Adiraju, Kiran A. V. "Synthesis and characterization of organic-inorganic colorants." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Soboyejo, N. O. "Disperse dyes derived from brominated 1,4-amino- or hydroxy-substituted anthraquinones." Thesis, University of Bradford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371497.
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Yu, Shun. "Molecular Interaction of Thin Film Photosensitive Organic Dyes on TiO2 Surfaces." Doctoral thesis, KTH, Materialfysik, MF, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-47354.
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The photosensitive molecule adsorption on titanium dioxide (TiO2) forms the so-called “dye sensitized TiO2” system, a typical organic/oxide heterojunction, which is of great interest in catalysis and energy applications, e.g. dye-sensitized solar cell (DSSC). Traditionally, the transition metal complex dyes are the focus of the study. However, as the fast development of the organic semiconductors and invention of new pure organic dyes, it is necessary to expand the research horizon to cover these molecules and concrete the fundamental understanding of their basic properties, especially during sensitization.In this work, we focus on two different photosensitive molecules: phthalocyanines and triphenylamine-based dyes. Phthalocyanines are organic semiconductors with symmetric macro aromatic molecular structures. They possess good photoelectrical properties and good thermal and chemical stability, which make them widely used in the organic electronic industries. Triphenylamine-based dyes are new types of pure organic dyes which deliver high efficiency and reduce the cost of DSSC. They can be nominated as one of the strong candidates to substitute the ruthenium complex dyes in DSSC. The researches were carried out using classic surface science techniques on single crystal substrates and under ultrahigh vacuum condition. The photosensitive molecules were deposited by organic molecular beam deposition. The substrate reconstruction and ordering were checked by low energy electron diffraction. The molecular electronic, geometric structures and charge transfer properties were characterized by photoelectron spectroscopy, near edge X-ray absorption fine structure spectroscopy and resonant photoelectron spectroscopy (RPES). Scanning tunneling microscopy is used to directly image the molecular adsorption.For phthalocyanines, we select MgPc, ZnPc, FePc and TiOPc, which showed a general charge transfer from molecule to the substrate when adsorbed on rutile TiO2(110) surface with 1×1 and 1×2 reconstructions. This charge transfer can be prevented by modifying the TiO2 surface with pyridine derivatives (4-tert-butyl pyridine (4TBP), 2,2’-bipyridine and 4,4’-bipyridine), and furthermore the energy level alignment at the interface is modified by the surface dipole established by the pyridine molecules. Annealing also plays an important role to control the molecular structure and change the electronic structure together with the charge transfer properties, shown by TiOPc film. Special discussions were done for 4TBP for its ability to shift the substrate band bending by healing the oxygen vacancies, which makes it an important additive in the DSSC electrolyte. For the triphenylamine-based dye (TPAC), the systematic deposition enables the characterization of the coverage dependent changes of molecular electronic and geometric structures. The light polarization dependent charge transfer was revealed by RPES. Furthermore, the iodine doped TPAC on TiO2 were investigated to mimic the electrolyte/dye/TiO2 interface in the real DSSC.The whole work of this thesis aims to provide fundamental understanding of the interaction between photosensitive molecules on TiO2 surfaces at molecular level in the monolayer region, e.g. the formation of interfacial states and the coverage dependent atomic and electronic structures, etc. We explored the potential of the application of new dyes and modified of the existing system by identifying their advantage and disadvantage. The results may benefit the fields of dye syntheses, catalysis researches and designs of organic photovoltaic devices.QC 20111114
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Alema, Fikadu Legesse. "Organic-inorganic hybrid doped with rhodamine dyes for light emitting applications." Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/2291.
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Mestrado em Ciência e Engenharia de MateriaisMateriais híbridos orgânico-inorgânicos dopados com corantes orgânicos, rodamina 6G e B (R6G e RB), foram caracterizados por espectroscopia de absorção, fotoluminescência e difracção de raios-X. As matrizes são constituídas por redes siliciosas covalentemente ligadas por pontes de ureia a nove unidades de oxietileno (CH2CH2O) e são conhecidas como material híbrido di-ureasil. Os padrões de difracção dos pós e os espectros de fotoluminescência mostram que os corantes orgânicos se encontram fortemente associados ao domínio do material híbrido diureasil. Os espectros de emissão registados para amostras dopadas com corantes de baixa concentração (0.008%) apresentam duas bandas de emissão na gama de baixo e alto comprimento de onda. Estas duas bandas de emissão são provenientes do híbrido di-ureasil e dos corantes indicando que ambos são materiais opticamente activos. Quando a concentração dos corantes é aumentada de 0.008% para 0.1% são feitas duas observações. A primeira indica que a emissão proveniente do híbrido di-ureasil a baixa concentração foi suprimida. Isto exprime claramente que existe uma forte transferência de energia do híbrido di-ureasil para as moléculas de corante. Os espectros de excitação do di-ureasil e do corante também confirmam a presença de transferência de energia do híbrido para o corante. A segunda consiste no facto de que a emissão proveniente do corante é deslocada para o vermelho e a banda é acompanhada por desdobramentos. Isto mostra a presença de mais do que um componente emissor devido a diferentes tipos de agregados de corante. Esta evidência é também confirmada por espectroscopia de absorção uma vez que o pico de absorção é deslocado para o vermelho com a concentração. O aumento nas intensidades de emissão dos materiais é também observado com o aumento na concentração dos corantes. Isto foi manifestado também no rendimento quântico absoluto de emissão dos materiais. Os rendimentos quânticos absolutos de emissão de 65% para amostras dopadas com RB e de 70% para amostras dopadas com R6G com concentração de 0.1% indicam que os materiais híbridos têm elevado rendimento quântico de emissão, colocando-os como candidatos para aplicações de emissão de luz. O resultado de XRD exibe um padrão idêntico ao padrão de difracção do di-ureasil não dopado indicando que o corante incorporado não altera as características estruturais dos diureasil não dopados. No entanto, a posição 2q significativa da interferência de difusão interparticular do domínio silicioso num meio polimérico [28] é deslocada para um valor inferior em 1.5º. Isto sugere que os corantes orgânicos são incorporados no domínio orgânico do híbrido di-ureasil.
Organic-inorganic hybrid materials doped with organic dyes, rhodamine 6G and B (R6G and RB), were characterized with absorption spectroscopy, photoluminescence, and X-ray diffraction techniques. The host matrix is a silica-based network to which nine oxyethylene (CH2CH2O) repeat units are covalently grafted by urea linkages and is known as di-ureasil hybrid material. The x-ray powder diffraction patterns and photoluminescence spectra show that the organic dyes are entrapped strongly in the organic domain of the di-ureasil hybrid material. The emission spectra recorded for samples doped with dyes of low concentration (0.008%) have two emission bands at low and high wavelength ranges. These two emission bands are due to the emissions both from the di-ureasil hybrid and the dyes indicating that both the host and the guest are optically active materials. When the concentration of the dyes increase from 0.008% to 0.1% there are two things observed. The first one is that the emission from the di-ureasil hybrid is suppressed from where it existed when the concentration was low. This clearly indicates that there is strong energy transfer from the di-ureasil hybrid to the dye molecules. The excitation spectra of the di-ureasil and the dye further confirmed the presence of an energy transfer from the host to the dye. The second thing was that the emission from the dye was observed red shifted and the band was accompanied by shoulders. This shows the presence of more than one emitting components which are due to different types of dye aggregates. This is also confirmed by the absorption spectroscopy as the absorption peak is red shifted with concentration. The increase in the emission intensities of the materials is also observed with the increase in the concentration of the dyes. This was also manifested in the absolute emission quantum yield of the material. The absolute emission quantum yields of 65% for RB and 70% for R6G doped samples with concentration of 0.1% signify that the hybrid materials have large emission quantum yield which put them as candidates for light emitting applications. The XRD result shows a pattern similar with the diffraction pattern of neat di-ureasil hybrid material indicating that the incorporated dye does not alter the structural features of the neat diureasil. Nonetheless, a 2q position signifying the interparticle scattering interference of the siliceous domain in a polymer rich medium [28] is shifted to lower value by 1.5º. This suggests that the organic dyes are incorporated in the organic domain of the di-ureasil hybrid.
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Beveridge, Allan John. "Ab initio calculations of organic molecules : substituted ethylenes, azoles and merocyanine dyes." Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/10797.
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Reeve, James Edward. "Functional dyes as tools for neurophysiology." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:8d8e7fa1-0f1d-4ff5-9f90-6915b15c1ad4.
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The aim of the project described in this thesis is to synthesise new functional molecules which interact with light for neurophysiological applications. In particular, I describe a family of amphiphilic porphyrins with large first hyperpolarisabilities which are used as SHG contrast agents and voltage-sensitive probes. In addition I detail a methodological microscopy tool and a novel caged form of a neuronal ion-channel antagonist. Chapter 1 introduces the key concepts underlying the use of dyes as SHG contrast agents. In particular it focuses on aspects of molecular design, covering both the amphiphilicity and nolinearity required by the target molecule. It covers quantification of the nonlinear properties of SHG stains, then surveys a number of examples which showcase the flexibility of SHG imaging as a biomedical technique. Chapter 2 describes a family of amphiphilic porphyrins with large first hyperpolarisabilities. Working from the structure-property relationships identified in Chapter 1, we fully characterise these dyes and demonstrate that they can be used in SHG imaging. We demonstrate that these molecules may also be tuned by complexation of a metal ion which can modulate their photophysical and solubility behaviour. Chapter 3 provides a description of how to determine the orientational distribution of dipolar dyes in a membrane by multiphoton microscopy. We measure the signal intensity of the dye in a model membrane system then find distributional moments which lead to the distribution itself. Chapter 4 explores whether off-axis contributions to the first hyperpolarisability tensor can significantly augment the dominant on-axis contribution from the main dipolar charge-transfer band. We synthesise and characterise a series of cis-donor cis-acceptor porphyrin compounds and explore their biophysical characteristics. Chapter 5 is the culmination of this project and after discussing method development, goes on to show how we measure the voltage sensitivity of an amphiphilic porphyrin SHG dye. We compare the archetypal porphyrin dye chromophore with three commercially available styryl dyes and demonstrate that our dye has greater sensitivity and a more rapid response. Chapter 6 describes a side project, the use of a photolabile cage to protect MK801, a neuronal ion-channel antagonist. By developing a water soluble photolabile cage using molecular design techniques, we are able to release MK801 in neurons with precise spatiotemporal control, allowing us to pinpoint the locus of two key neurophysiological processes.
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Oxspring, Darren A. "The detection and determination of selected organic pollutants by modern instrumental techniques of analysis." Thesis, University of Ulster, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241679.
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Gould, David Matthew. "Bleaching of dyes by hydrogen peroxide using oxo- and polyoxo-metalates as catalysts." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325604.
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Mallabon, Caroline M. "The metalloporphyrin-catalysed oxidation of azo dyes in aqueous solution using hydrogen peroxide." Thesis, University of York, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341108.
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Velardo, Amalia. "Small organic molecules for next generation electronics." Doctoral thesis, Universita degli studi di Salerno, 2016. http://hdl.handle.net/10556/2215.
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2014 - 2015In this PhD thesis attention has been focused on the theoretical design of organic small molecules for next generation electronics. The task of this thesis has concerned with the theoretical analysis of the operational performances of small dyes in photovoltaic solar cells, both in bulkheterojunction and dye sensitized solar cells; with particular emphasis on the theoretical analysis of the rates of the elementary electron transfer processes. A full quantum mechanics procedure for computing the rates of elementary electron transfer processes has been developed. The procedure starts from the Fermi Golden Rule (FGR) expression of the rate of electronic transitions and makes use of a rigorous evaluation of the Franck-Condon weighted density of states, performed by Kubo’s generating function approach. The analysis of electron transfer rates has revealed to be a very powerful tool for investigating structure-property relationships for the employment of small organic molecules in photovoltaic solar cells. The methodology has been applied to a class of small organic molecules, which show different power energy conversion efficiencies. The different efficiencies of the dyes have been attributed to very different rates of photoinduced electron transfer, the first step of energy conversion process in any type of photovoltaic solar cell. The last part of this thesis has been devoted to a very important task for next generation electronics: the rational design of new N-rich fused-ring heteroaromatics small organic molecules for n-type charge transport in thin layers. The substitution of CH units with nitrogen atoms is particularly appealing because, it offers the possibility of tuning the electron donor/acceptor character of the molecule. [edited by author]
XIV n.s.
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Wong, Yin. "Synthesis and characterization of substituted poly(dibenzofulvenes) and some novel fluorescent dyes." HKBU Institutional Repository, 2011. https://repository.hkbu.edu.hk/etd_ra/1301.
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Ullmann, Dagny Anna. "Measurements of diffusion coefficients of organic dyes in proxies of atmospheric particles." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/61969.
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Shipman, Patrick Oliver. "The design of organoiron and organic polymers containing azo dyes and calixarenes." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/18821.
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Organic azo dye polymers are prepared from the ring-opening metathesis polymerization of azo dye functionalized norbornenes. These polymers are examined for their trans-cis¬ isomeration, UV-visible properties, and their acid sensing capabilities. The organoiron polymers are prepared through polycondensation reactions between organoiron azo dye complexes and O-, S-, or N-containing dinucleophiles. These polymers are analyzed for their thermal and UV-visible properties.
The synthesis and characterization of upper rim functionalized calix[4]arenes are described. Calix[4]arenes containing propanol groups on either the 5- or both the 5- and 11- positions were prepared. These calixarenes also contained either: phenolic, propoxy, or t-butyl-dimethyl-siloxy groups on the lower rim. These calixarenes were reacted with chloro-terminated organoiron carboxylic acid complexes to prepare metallocalix[4]arenes containing one, two, or four metal centres on their upper rims. The metallocalix[4]arenes were used to prepare calix[4]arene containing azo dyes, or ferrocenes. These metallocalix[4]arenes were also used to prepare organoiron based polycalixarenes. Organic polymers were also prepared from the organic upper rim propanol functionalized calix[4]arenes. The metallocalix[4]arenes were additionally studied for their electrochemical properties. The azo dye containing metallocalix[4]arenes were studied for their UV-visible properties and acid sensing capabilities. The polycalix[4]arenes were additionally studied through gel permeation chromatography, thermal gravimetric analysis and differential scanning calorimetry.
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Cohanoschi, Ion. "THREE-PHOTON ABSORPTION PROCESS IN ORGANIC DYES ENHANCED BY SURFACE PLASMON RESONANCE." Doctoral diss., University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3891.
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Multi-photon absorption processes have received significant attention from the scientific community during the last decade, mainly because of their potential applications in optical limiting, data storage and biomedical fields. Perhaps, one of the most investigated processes studied so far has been two-photon absorption (2PA). These investigations have resulted in successful applications in all the fields mentioned above. However, 2PA present some limitations in the biomedical field when pumping at typical 2PA wavelengths. In order to overcome these limitations, three-photon absorption (3PA) process has been proposed. However, 3PA in organic molecules has a disadvantage, typical values of σ3' are small (10-81 cm6s2/photon2), therefore, 3PA excitation requires high irradiances to induce the promotion of electrons from the ground state to the final excited state. To overcome this obstacle, specific molecules that exhibit large 3PA cross-section must be designed. Thus far, there is a lack of systematic studies that correlate 3PA processes with the molecular structure of organic compounds. In order to fill the existent gap in 3PA molecular engineering, in this dissertation we have investigated the structure/property relationship for a new family of fluorene derivatives with very high three-photon absorption cross-sections. We demonstrated that the symmetric intramolecular charge transfer as well as the -electron conjugation length enhances the 3PA cross-section of fluorene derivatives. In addition, we showed that the withdrawing electron character of the attractor groups in a pull-pull geometry proved greater 3PA cross-section. After looking for alternative ways to enhance the effective σ3' of organic molecules, we investigated the enhancement of two- and three-photon absorption processes by means of Surface Plasmon. We demonstrated an enhancement of the effective two- and three-photon absorption cross-section of an organic compound of 480 and 30 folds, respectively. We proved that the enhancement is a direct consequence of the electric field enhancement at a metal/buffer interface. Next, motivated by the demands for new materials with enhanced nonlinear optical properties, we studied the 3PA of Hematoporphyrin IX and J-aggregate supramolecular systems. As a result, we were able to propose the use of 3PA in photodynamic therapy using Photofrin, the only drug approved by the FDA for PDT.Ph.D.
Other
Optics and Photonics
Optics
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Click, Kevin A. "Design and Synthesis of Organic Dyes for Solar Energy Conversion and Storage." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492448144094887.
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Hsuan, Chang Huan, and 張桓瑄. "Dialkylphenyl-Containing Organic Dyes for Dye-Sensitized Solar Cells." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/77329022061152143578.
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Wei-Ting, Chen, and 陳薇婷. "Organic Dyes for P-type Dye-Sensitized Solar Cell." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/21798347849532686059.
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碩士國立臺灣師範大學
化學系
99
A series of dyes (PT) with a carboxylic acid-conjugated spacer-donor-conjugated space-acceptor skeleton have been synthesized and used as the sensitizer for p-type dye-sensitized solar cells (DSSCs). Structural variation of the dye has significant influence on the photophysical and electrochemical properties of the dyes, and the incident photon-to-current conversion efficiencies of the DSSCs. DSSCs based on the sensitizers with two anchoring groups have more efficient hole injection and less dark current, and therefore higher Voc and Jscvalues those based on the dyes with only one anchoring group. Dark current and electrochemical impedance spectroscopy (ESI) were measured to rationalize the cell efficiencies. The efficiencies of the p-type devices based on PT series range from 0.043% to 0.081%. These values reach 49−92% of the standard device based on S(4-(bis(4-(5-(2,2-dicyanovinyl)thiophen-2-yl)phenyl)amino)benzoic acid) fabricated and measured under similar conditions.
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Liao, Shao-Hong, and 廖紹宏. "Organic dyes-sensitized solar cells." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/97653494150553138831.
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碩士國立高雄大學
化學工程及材料工程學系碩士班
97
In this work, carbazole-triphenylamine (CTPA)-based metal-free organic dyes were synthesized and employed to the dye-sensitized solar cells (DSSCs). Metal-free organic dye, compared to the ruthenium-based photo-sensitizer in the Grätzel cell, has the advantages of high absorbance coefficient and without using expensive metal. We employed few kinds of organic synthesis methods. Different number of aldehyde groups were first linked on the TPA molecule by using the Vilsmeier-Haack reaction. Then, three different carbazole-triphenylamine-based structures were obtained using the bromination of aromatic derivatives and Suzuki coupling reaction, which possess different numbers of aldehyde and carbazole groups. Finally, the metal-free organic dyes were obtained through the nucleophilic addition and dehydration between the aldehyde groups on CTPA and the methylene of rhodanine-3-acetic acid by using the Knoevenagel condensation reaction. The above three dyes were anchored on the surface of titanium dioxide nanoparticles via the carboxylic acid of dyes by using the self-assembly method. Furthermore, these dyes were used to assemble the dye-sensitized solar cells and the performance of the cells was measured. The optimal efficiency of DSSCs reaches to 4.64% for CTPAR2 dye.
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Huang, Shin-Tang, and 黃勢棠. "Metal-Free Organic Dyes for Efficient Dye-Sensitized Solar Cell." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/fnh8g6.
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碩士中國文化大學
應用化學研究所
96
Two series (Cy and An) of dyes containing a cyanovinyl entity and an anthracene with alkoxy substituents at the 9 and 10 positions, respectively, as the spacer have been synthesized and characterized. Dye-sensitized solar cells (DSSCs) using these dyes as the sensitizers exhibited good efficiencies. The efficiencies of the devices based on Cy series range from 3.48-4.92%, and those based on An series range from 4.17-4.69%. These values which reach 45-70% and 59-67%, respectively, with respect to that of N719-based device fabricated under similar conditions. In general, a better DSSC performance was achieved in molecules with a shorter molecular structure and higher light harvesting. The cyanovinyl entity (Cy series), especially in the long molecular structure, where the cyanovinyl group is away from the electron donating amine by two or more aromatic groups, may behave as a charge trap. This argument was supported by theoretical computations. A positive correlation could be obtained from the theoretically calculated product of oscillator strengths and the charge shift at the cyanoacrylic acid group and the short-circuit currents in the DSSCs. The rigid anthracene segment in An series compounds. The anthracene with alkoxy substituents may cause thiophene moiety hamper the charge transfer and results in lower open-circuit voltages and short-circuit currents of the solar cells.
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Hsieh, Jung-Hang, and 解榮航. "Organic Dyes with Dithiafulvalene Donors for Dye-Sensitized Solar Cells." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/95283333877463801481.
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碩士國立臺灣師範大學
化學系
104
We have successfully developed a new series of D-π-A types organic dyes containing dithafulvalene(DTF) units as the electron donor, 8H-indeno[2,1-b]thiophen-8-one as the core of the conjugated spacer, and 2-cyanoacrylic as the acceptor and anchor. These dyes were used as the sensitizers for dye sensitized solar cell applications. Thiophene or bithiophene was also introduced to the spacer to tune the conjugation. Different alkyl chains were also incorporated at the DTF moiety. Stille Coupling, Grignard reaction, Vilsmeier–Haack reaction, and Knoevenagel condensation were the key reactions used to construct the dye molecules. Electronic properties such as absorption and emission spectra, and electrochemical property such as cyclic voltammetry of the dyes were also investigated. The dyes have high molar extinction absorption in 400 to 600 nm region. The efficient of DSSC device based on DTF-1 sensitizer can be reached 4.48%. After adding CDCA as the co-adsorbent, the efficiency was further improved to 5.53%, reaching~67% of the standard cell fabricated from N719.
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Chang, Yu-Cheng, and 張羽成. "Synthesis of Novel Organic Dyes for Dye Sensitized Solar Cells." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/eat658.
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碩士國立臺北科技大學
有機高分子研究所
97
In this thesis, organic dyes with the structure of donor-conjugated chain-acceptor (D-π-A) have been synthesized for dye-sensitized solar cell (DSSC) application. The electron donating and accepting groups are arylamine and cyano acrylic acid , respectively. All of these compounds were characterized by UV/VIS spectrophotometer, fluorescence spectrophotometer and cyclic voltammetry. The photo-conversion results of their DSSC devices were inspected using the AM 1.5 simulated solar light system.
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Sie, Cheng-Min, and 謝承旻. "Synthesis of Novel Organic Dyes for Dye Sensitized Solar Cells." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/a8yz5n.
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碩士國立臺北科技大學
有機高分子研究所
97
In this thesis, the organic dyes with the structure of donor-conjugated chain-acceptor have been synthesized for dye sensitized solar cell (DSSC) application. The electron donating group is arylamine with thiophene, and the electron accepting group is cyanoacrylic acid. All compounds were characterized by UV-vis spectrophotometer, fluorescence spectrophotometer, and cyclic voltammetry. The power-conversion efficiency was measured by the AM1.5 simulated solar light system.
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Lee, Yi-ting, and 李怡葶. "Spirofluorenebithiophene containing organic dyes for DSSCs." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/61778773044227819356.
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碩士國立中央大學
化學研究所
97
New organic dyes that contain spiro [cyclopenta[2,1-b:3,4-b''] dithiophene-4,9''-fluorene] conjugate spacer between arylamine donor (diphenylamine, bis(4-methoxyphenyl) amine and carbazol) and the cyanoacrylic acid acceptor have been synthesized. These compounds are characterized by 1H NMR, 13C NMR, mass spectrometry, UV / visible spectrometer, fluorescent spectrometer and cyclic voltametry in the estimation of HOMO and LUMO energy levels. These dyes were developed as the sensitizers for the application in dye-sensitized TiO2 nanocrystalline solar sells (DSSCs). A power conversion efficiency (ηPCE) of 3.4 % was determined with the DSSC based on 6-(5-(4-(9H-carbazol-9-yl)phenyl)thiophen-6-yl)spiro[cyclopenta[2,1-b:3,4-b’]dithiophene-4,9’-fluorene]-2-cyanoacrylic acid (SCZ) under simulated AM 1.5 G irradiation (100 mW / cm2): short-circuit current density (Jsc) of 8.65 mA cm-2; open-circuit voltage (Voc) of 0.57 V; fill factor (FF) of 0.70. The experimental results show that the DSSC dyes possess spirofluorenyl group enhance the photo-stability, molar extinction coefficient, and the red-shifting of UV-visible absorption wavelength. Nevertheless, compared with the bithiophene centered DSSC dyes, the steric hindrance of the spirofluorenyl group impedes the dye adsorption on TiO2 and hence decrease the power conversion efficiency of DSSCs.
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Yang, Fong-Ming, and 楊豐銘. "Dyes for BODIPY Organic solar cells." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/81028964483490848911.
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