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1
Zhang, Lei. "Structure-property relationships of azo dyes for dye-sensitized solar cells." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708314.
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Wills, Kathryn. "Copper dyes for dye-sensitized solar cells." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636545.
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This thesis studies the application of copper(I) complexes as the sensitizing component of dye sensitized solar cells (DSCs). Ruthenium(II) polypyridyl complexes have been widely studied and shown great success for the past two decades; however the metal is rare and expensive. A copper(I) based DSC could offer a viable alternative to using ruthenium(II) dyes, taking into account the cost and sustainability advantages. Interest in copper(I) DSCs has reignited over the past five years and the work in this thesis begins by reproducing the synthesis of one of the first reported complexes, [Cu(6,6’-dimethyl-2,2’-bipyridine-4,4’-dicarboxylic acid)2][Cl]. A more detailed study of the dye and its properties will be described, including assessing the effect of TiO2 film dye time on DSC performance, electrochemical studies and coupling the dye with a Co2+/3+ mediator. In the following chapters, improvements to the basic 2,2’-bipyridine framework are investigated. An experimental and computational investigation with a [Cu(2,2'-biquinoline-4,4'-dicarboxylic acid)2][HNEt3] complex is presented, where the 2,2’-biquinoline ligand has been chosen as a bulkier, more conjugated alternative to the 2,2’-bipyridine ligand. Although DSC efficiencies with this complex are comparatively low, an investigation into possible reasons for this is described. This thesis then considers functionalisation of a 2,2’-bipyridine ligand with halide and thiophene substituents. Several new ligands and copper(I) complexes are described and characterised. A top DSC efficiency of 1.41% was obtained with a [Cu(6,6'-dimethyl-[2,2'-bipyridine]-4,4'-diyl)bis(thiophene-2-carboxylic acid)2][PF6] dye. The synthetic route towards this complex and an analysis of its features, such as emissive behaviour, electrochemical properties and electron diffusion length, are described.
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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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Torpner, Jessie, and Elvira Boman. "Characterization of Natural Peruvian Dyes on Dye-Sensitized Solar Cells." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-326414.
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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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Mohsen, Moneer Kadhm. "Synthesis and testing of new dyes for dye-sensitized solar cells." Thesis, Bangor University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.664480.
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This thesis concentrates on the development and synthesis of new metal-containing phthalocyanine and metal-free organic dyes for dye-sensitized solar cells (DSC). In this thesis attempts have been made to cover a broad region of visible light through the synthesis of three different dye families. The N719 is the common dye was used as a sensitizer in DSC devices, which absorbs at 450-600 nm, while in this thesis were synthesized and developed three new types of dyes to work either side of N719 absorb light at (400-450) run for yellow and red single or di-linker dyes, cyanine and phthalocyanine dyes which absorb higher than 600 run. This thesis consists of six chapters. Chapter one includes a short history and introduction to dye-sensitized solar cells with a description of triarylamine, phthalocyanine and cyanine dyes, which are related to this thesis work.
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Siu, Chi Ho. "Metallated and metal-free molecular dyes for dye-sensitized solar cells." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/96.
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The molecular design, synthesis and spectroscopic characterization of a series of ruthenium(II), metal-free and platinum(II) photosensitizers were discussed. The applications of some of these compounds in dye-sensitized solar were also outlined. To start with, a brief overview on the background of dye-sensitized solar cells (DSSCs) was presented in Chapter 1. In Chapter 2, a series of new thiocyanate-free ruthenium(II) cyclometalated complexes with different ligands were successfully synthesized and some of them were fully characterized by spectroscopic and computational methods. The nature of cyclometalating ligands effectively tunes the properties of the metal complexes and the resulting DSSC performance. In Chapter 3, new di-anchoring organic dyes have been synthesized and characterized. This molecular design strategy can significantly enhance the . value because this successfully inhibits the undesirable charge combination and prolongs the electron lifetime. The discoveries open up a new avenue to the evolution of organic sensitizers and the optimization of bridged di-anchoring dyes for highly efficient co-adsorbent-free DSSCs. In Chapter 4, a series of new thiophene-free platinum sensitizers for the application of DSSCs was developed. Four unsymmetrical platinum(II) di-acetylide complexes containing phenothiazine moiety with different donor units were designed and synthesized. These photosensitizers were fully characterized by spectroscopic as well as computational studies and also successfully employed in DSSC fabrication. These findings provided positive evidence that platinum-acetylide complexes have a great potential and prospect for the use as promising metal-based photosensitizers in DSSC applications. Finally, Chapters 5 and 6 present the concluding remarks and the experimental details of the work described in Chapters 2–4.
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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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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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Fattori, Alberto. "Electrochemical and spectroelectrochemical studies of dyes used in dye-sensitized solar cells." Thesis, University of Bath, 2010. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538162.
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Electrochemical and spectroelectrochemical techniques were employed to investigate the redox characteristics of dyes for dye sensitized solar cells (DSCs) adsorbed at the surface of fluorine-doped tin oxide (FTO) and FTO TiO2 electrodes. In this work are studied Ru-based dyes such as cis-bis(isothiocyanato)-bis(2,2’-bipyridyl- 4,4’dicarboxylato)-ruthenium(II) (N719) and (cis-RuLL'(SCN)2 with L=4,4'- dicarboxylic acid-2,2'-bipyridine and L'=4,4'-dinonyl-2,2'-bipyridine) known as Z907, and indoline organic dyes coded as D102, D131, D149, and D205. The adsorption, diffusion and stability of adsorbed dyes were studied using cyclic voltammetry in acetonitrile and 0.1 M NBu4PF6. The adsorption technique at FTO electrodes was optimized in order to be reproducible so that electrochemical studies as a function of dye coverage were carried out. Langmuirian binding constants were approximately estimated for all dyes adsorbed at FTO electrodes. Rate constants for the chemical degradation of the oxidized dye were also obtained. Is shown that degradation of the dyes mainly occurs at the surface of FTO and only insignificant degradation is evident once the dyes are adsorbed on TiO2. The degradation of dye adsorbed on FTO is shown to affect charge transport from the nonporous TiO2 via electron hopping. Spectroelectrochemical studies of indoline dyes adsorbed on FTO/TiO2 electrodes revealed a red shift of absorption peaks after oxidation and the presence of a strong charge transfer band in the near IR that suggest delocalization of holes in the dye layer. This is consistent with observation that the diffusion coefficient for hole conduction in the adsorbed dye layer is several orders of magnitude higher for the organic dyes compared to the Ru-based dyes. DSCs fabricated using indoline dyes showed good performance. Incident photon-tocurrent conversion efficiency (IPCE) spectra and I-V characteristics are presented.
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Low, Kian Sing. "Structure-property relationships of dyes as applied to dye-sensitized solar cells." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.607807.
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Gong, Yun. "Structure-property relationships of dyes as applied to dye-sensitized solar cells." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/275007.
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This work investigates the correlation of structural and photovoltaic properties of dyes used in dye-sensitized solar cells. Experimental methods, including ultraviolet-visible spectroscopy, fluorescence spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy are employed to study optical and electrochemical properties of dye molecules. Computational methods, including density functional theory and time-dependent density functional theory, are used to validate and predict the optical and electronic properties of dye molecules, in their isolated state and once embedded into a working electrode device environment that comprises a dye...TiO2 interface. The results chapters begin with the presentation of a series of quinodimethene dyes that are experimentally validated for their photovoltaic application, and associated computational studies reveal that an inner structural factor - a phenyl ring rotation occurring during the optical excitation process - leads to the competitive photovoltaic device performance of these dyes. Carbazole-based dyes are then systematically studied by computation, especially considering charge transfer paths and binding modes of these dyes on a titania surface. The theoretical models for the basic building block of this chemical family of dyes, known as MK-44, successfully support and explain structural discoveries from X-ray diffraction and reflectometry that impact of their function. A benzothiadiazole-based dye, RK-1, is then systematically studied by both experimental and computational methods, and the results show that the π-bridge composed of thiophene, benzothiadiazole and benzene rings leads to excellent charge separation; and the rotation of these rings during the optical excitation process may well be consistent with the fluorescence spectrum. Finally, the well-known ruthenium-based dyes are theoretically studied to determine the properties of different ligands connected to the metal core of the complex. Conformations with different NCS ligands are calculated in terms of energy and explain well the corresponding results from X-ray diffraction. Acid-base properties of carboxyl groups connected to pyridine ligands in N3 and N749 are theoretically calculated based on thermodynamics and density functional theory. Implicit and explicit models are both adopted to predict these acid dissociative constant values, which are generally in a good agreement with the reported experimental data. The thesis concludes with conclusions and a future outlook.
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Hart, Aaron S. "Substitution Effects of Phenothiazine and Porphyrin Dyes in Dye-sensitized Solar Cells." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc407837/.
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The details of dye sensitized solar cells was explained and phenothiazine and porphyrin based dyes were synthesized for use in DSSCs. DSSCs offer a unique and cost effective method of renewable energy. DSSCs are characterized through various tests, with the overall efficiency, η, bearing the greatest importance. Incident photon to current conversion efficiency, or IPCE, is also another important characterization of DSSCs. Effect of positioning of the cyanoacrylic acid anchoring group on ring periphery of phenothiazine dye on the performance of dye sensitized solar cells (DSSCs) is reported. The performances of the cells are found to be prominent for solar cells made out of Type-1 dyes compared to Type-2 dyes. This trend has been rationalized based on spectral, electrochemical, computational and electrochemical impedance spectroscopy results. Free-base and zinc porphyrins bearing a carboxyl anchoring group at the para, meta, or ortho positions of one of the meso-phenyl rings were synthesized for DSSCs. Photoelectrochemical studies were performed after immobilization of porphyrins onto nanocrystalline TiO2. The performance of DSSCs with the porphyrin anchoring at the para or meta position were found to greatly exceed those in the ortho position. Additionally, zinc porphyrin derivatives outperformed the free-base porphyrin analogs, including better dye regeneration efficiency for the zinc porphyrin derivatives and for the meta and para derivatives through electrochemical impedance spectroscopy studies. The overall structure-performance trends observed for the present porphyrin DSSCs have been rationalized based on spectral, electrochemical, electrochemical impedance spectroscopy and transient spectroscopy results.
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Sampaio, Samuel Gondim. "Study and Characterization of New Natural Dyes for Application in Sensitized solar cells." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11335.
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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoEste trabalho apresenta um estudo e caracterizaÃÃo de corantes com flores de plantas coletadas na regiÃo Nordeste do Brasil, tais como: a Sida cordifolia (malva branca), a Catharanthus roseus (boa noite) e a Torenia fournieri (amor-perfeito-de-verÃo), Allamanda catÃrtica (alamanda da flor grande) e Cobaea scandens (sino de catedral). Foi estudado e observado a influÃncia dos flavonoides na sensibilizaÃÃo dos corantes naturais por meio de um protÃtipo de cÃlula fotovoltaica, com vidros condutores com um filme de SnO2:F produzidos por spray PirÃlise. As plantas foram submetidas a um tratamento de lavagem. Foram maceradas e imersas em um solvente extrator. ApÃs alguns dias, foram concentradas no rotaevaporador a uma velocidade 160 rpm em temperatura ambiente por 40 minutos. Este corante foi aplicado sobre uma camada de TiO2 e entÃo a cÃlula foi testada sob a luz solar. Os valores obtidos foram: Torenia fournieri, corrente de curto-circuito = 0,44 mA e tensÃo de circuito aberto = 0,16 V; Catharanthus roseus, corrente de curto-circuito = 0,43 mA e tensÃo de circuito aberto = 0,14 V; Sida cordifolia, corrente de curto-circuito = 0,22 mA e tensÃo de circuito aberto = 0,19 V; Allamanda catÃrtica, corrente de curto-circuito = 0,19 mA e tensÃo de circuito aberto = 0,12V; Cobaea scandens, corrente de curto-circuito = 0,32 mA e tensÃo de circuito aberto = 0,17V. Estes resultados podem fornecer mais dados para melhor entendimento e uso de novos corantes naturais em cÃlulas solares.
This paper presents a study and characterization of dyes with flowers of plants collected in the Northeast of Brazil, such as Sida cordifolia (malva branca), the Catharanthus roseus (boa noite), Torenia fournieri (amor-perfeito-de-verÃo), Alamanda cathartic (alamanda da flor grande) and Cobaea scandens (sino de catedral). Was studied and observed the influence of flavonoids in the sensitization of natural dyes by means of a prototype solar cell with conductive film with a glass of SnO2: F produced by spray pyrolysis. The conductive glass was obtained precursor solution (HCl/H2O) containing of tin II chloride dihydrate (SnCl2.2H2O), ammonium fluoride (NH4F) and a slide glass heated to 600 Â C. The solution was sprayed on the heated substrate. About conductive glass was deposited a layer of titanium dioxide (TiO2). The layer was obtained by dissolving in commercial TiO2 powder acetic acid (CH3CO2H) and Triton X. The electrolyte was a solution of iodine / triiodide into the intracellular regeneration cycle, the counter electrode was a layer made of graphite. The plants were treated with a by washing with deionized water, drying with heat gun and Silica Gel to absorb moisture. Were macerated and immersed in an organic solvent. After a few days, were concentrated in a rotary evaporator at a speed 160 rpm at room temperature for 40 minutes. This dye was applied on the TiO2 layer and then the cell was tested under sunlight. The values obtained were: Torenia fournieri, short-circuit current = 0.44 mA and open circuit voltage V = 0.16; Catharanthus roseus, short-circuit current = 0.43 mA = 0 and open-circuit voltage, 14 V, Sida cordifolia, short-circuit current = 0.22 mA and open circuit voltage V = 0.19; Allamanda cathartic, short-circuit current = 0.19 mA and open circuit voltage V = 0.12; Cobaea scandens, short-circuit current = 0.32 mA and open circuit voltage = 0.17 V. These results may provide more data for better understanding and use of new natural dyes in solar cells.
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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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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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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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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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Park, Eunsol. "Synthesis of Tethering Group on Borylazadipyrromethene Dyes to Apply to Photogalvanic Dye-sensitized Solar Cells." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc700072/.
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This is my thesis research on the preparation of borylazadipyrromethene (azaBODIPY) dyes bearing an anchoring group, such as a carboxylic acid group, at the β-pyrrolic position of the azadipyrromethene scaffold. Carboxylate groups form covalent bonds to oxide semiconductors such as TiO2 (n-type) or Cu2O (p-type) in dye-sensitized solar cells (DSCs) or photogalvanic dye-sensitized solar cells (P-DSCs). Oxide-binding azaBODIPY dyes can be used to investigate the rate and mechanism of electron injection from the dyes to the semiconductors. Two different types of azaBODIPY (difluoroboryl and dialkynylboryl) were prepared by following previously developed methods. To convert difluoroborylazaBODIPY to the final dyes having a carboxylic acid in the β-pyrrolic position, several distinct synthetic routes were designed, adopting various reactions, such as halogenation, Sonogashira coupling, Knoevenagel condensation, Grignard reagents, Vilsmeir-Haack, and Steglich esterification. Some of these reactions were successful, but the overall synthesis to the targeted final molecule couldn’t be accomplished. Even though further studies on the synthesis of oxide-binding azaBODIPYs are needed, at least my thesis research suggests what reactions can be implemented to complete this synthesis in the future. Proton NMR (nuclear magnetic resonance) and carbon NMR were commonly used to confirm the synthesized compounds, and sometimes crystallographic information was obtained by XRD (X-ray diffraction) whenever crystals of sufficient size and quality were grown. NMR spectra, interpreted by SpinWorks 3 software, and crystal structures will be introduced in each chapter.
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Anderson, Assaf Y. "Quantifying regeneration in dye sensitized solar cells : a step toward red absorbing dyes having lower energy loss." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/6181.
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A limiting factor on DSSC efficiency is the lower fraction of the solar spectrum that is absorbed by the dye molecules developed to this point. Dye molecules that function well in DSSCs tend to have poor or no absorption to the red of 750 nm. Extending this absorption to the red by 100 nm, without losing efficiency in other ways, would result in a significant improvement in photocurrent. This challenge has proven difficult, in large part because of one slow reaction in the electron transfer cycle of DSSCs, the regeneration reaction. Better understanding of this reaction is thus critical. The kinetics of regeneration is understudied relative to the other processes in DSSCs, this is in part because the regeneration reaction produces no, as yet detected, measurable electrical signal. It must be studied by more difficult transient absorbance (TA) techniques. The first step of this thesis focuses on isolating a reliable transient signal that reflects the regeneration reaction. This is made by upgrading the conventional TA system to also acquire transient electrical (TE) signals simultaneously (TA-TE). The system is used to characterize dye-sensitized solar cells (DSSCs) under 1 sun illumination whilst the cells are fully operational and their stability is monitored. The second step of the work consists of the development of a methodology and a kinetic model which uses the isolated regeneration signal and a range of complimentary measurements on operating cells, to determine the quantum yield and the associated intrinsic rate constants and orders of the regeneration reaction. This enabled understanding of the regeneration mechanism and its optional rate limiting steps. Finally, the use of steady state photoinduced absorption (SSPA), as a complementary or alternative tool to assess regeneration, is also questioned. SSPA is compared with the regeneration TA –TE and charge extraction measurements.
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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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Neuthe, Katja [Verfasser]. "Synthesis and Characterization of Transition Metal-Based Dyes for the application in Dye Sensitized Solar Cells / Katja Neuthe." Berlin : Freie Universität Berlin, 2014. http://d-nb.info/1060717859/34.
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Rohwer, Egmont Johann. "Ultrafast photodynamics of ZnO solar cells sensitized with the organic indoline derivative D149." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86444.
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Thesis (PhD)--Stellenbosch University, 2014.ENGLISH ABSTRACT: The initial charge transfer from dye molecules' excited states to the conduction band of a semiconductor, after absorption of visible light by the former, is critical to the performance of Dye sensitized Solar Cells (DSC). In a ZnO-based DSC sensitized by the organic indoline derivative D149, the dynamics associated with charge transfer are investigated with femtosecond transient absorption spectroscopy. The time-resolved measurement of the photo-initiated processes reveal electron transfer rates corresponding to excited state lifetimes of 100s of fs, consistent with previously measured high absorbed photon to current conversion efficiencies. The photo-electrode measured as an isolated system shows decay times of bound electrons in excited states of the dye to be ~150 fs and shows the subsequent emergence of absorption bands of the oxidized molecules. When the I-/I-3 redox couple is added to the system, these excited state lifetimes change and are found to be dependent on the cation in the electrolytic solution. Small cations like Li+ reduce the excited state lifetime to sub-100 fs, whilst larger cations like the organic tetrabutylammonium result in longer lifetimes of 240 fs. The action of the electrolyte can be observed by the reduced lifetime of the oxidized dye molecules' absorption bands. The effect of operating parameters and changes in the production protocol of the DSC on the primary charge injection are also investigated and reported on.
AFRIKAANSE OPSOMMING: Die aanvanklike ladingsoordrag vanuit kleurstofmolekules' opgewekte toestande tot in die leidingsband van 'n halfgeleier, na absorpsie van sigbare lig deur eersgenoemde, is van kritiese belang vir die uitset van halfgeleier-gebaseerde sonkragselle wat met kleurstowwe vir absorpsie verhoging, gebind is. In hierdie werk word hierdie proses en verwante fotodinamika in die geval van 'n ZnO sonkragsel gekleur met indolien D149 ondersoek d.m.v femtosekonde-tydopgelosde absorpsiespektroskopie. Hierdie metings onthul elektron-oordragstempos wat ooreenstem met lewenstye van opgewekte toestande in die orde van 100 fs. Hierdie is met voorheen-bepaalde hoë foton-tot-stroom omskakelingsdoeltreffendheid ooreenkomstig. Die foto-elektrode, as geïsoleerde sisteem beskou, toon afvalstye van gebonde elektrone in opgewekte toestande van ~150 fs, en die gevolglike opkoms van absorpsie deur geoksideerde molekules word waargeneem. As die I-/I-3 redoks oplossing tot die sisteem bygevoeg word, verander die opgewekte toestande se afvalstye en toon 'n katioon-afhanklikheid. Klein katioone soos Li+ verkort die afvalstye tot onder 100 fs, terwyl groter katioone soos die organiese tetra-butielammonium langer afvalstye (240 fs) tot gevolg het. Die werking van die elektrolitiese oplossing kan waargeneem word deur die verkorte lewenstyd van die absorpsiebande wat aan die geoksideerde molekules toegeken is. Die uitwerking van operasionele parameter asook veranderinge in die produksie protokol op die primêre ladingsoordrag word ondersoek en verslag daarop word gelewer.
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Delices, Annette. "Organized Organic Dye / Hole Transporting Materials for TiO2- and ZnO- based Solid-State Dye-Sensitized Solar Cells (s-DSSCs)." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC066/document.
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En raison des problèmes d'instabilité à moyen termes des cellules solaires à colorant (DSSC), l'électrolyte liquide à base d'iodure a été remplacé par plusieurs types de matériaux solides transport de trous (HTM) pour obtenir des DSSCs à l'état solide (s-DSSCs). Parmi ces matériaux, l’utilisation des polymères conducteurs(PC) a attiré une attention considérable en raison de leur bonne stabilité, de leur haute conductivité et de la facilité de leur dépôt sur le semi-conducteur mésoporeux TiO2. Dans ce travail de thèse, plusieurs s-DSSCs basées sur des PC utilisés comme HTM ont été développés dans le but d'améliorer leurs performances photovoltaïques en tenant compte des deux objectifs suivants: (i) l'optimisation des processus de transfert inter facial de charge dans la cellule solaire, et (ii) l'optimisation du transport de charge dans le semi-conducteur d'oxyde de type n. Pour atteindre ces objectifs, chaque composant de la s-DSSC a été modifié afin d'étudier son effet sur les performances du dispositif final. En première tentative, une étude analytique est réalisée en faisant varier le sensibilisateur afin de déterminer les fragments de la structure du colorant, qui ont un effet important sur le processus de photopolymérization électrochimique in-situ (PEP) à la fois en milieu organique et en milieu aqueux mais aussi sur les performances des s-DSSCs. Sur la base de ces résultats, un nouveau concept a été développé et consiste en la suppression totale de l'interface entre le colorant et le HTM. Ceci est obtenu par la synthèse de nouveaux colorants liés de façon covalente à un monomère électroactif qui est co-polymérisé par la PEP in-situ. Le copolymère résultant, utilisé comme HTM, est lié de manière covalente au colorant. En outre, la nature de la liaison chimique, reliant le résidu triphénylamine TPA au monomère, est également étudiée comme un facteur clé dans les performances de s-DSSC. En outre, et pour optimiser les processus de transport de charges dans ce type de s-DSSC, de nouvelles s-DSSC basées sur ZnO ont été réalisées et étudiéesDue to instability problems of dye sensitized solar cells (DSSCs) in longtime uses, the iodine based liquidelectrolyte has been replaced by several types of solid hole transporting materials (HTM) to perform solidstate DSSCs (s-DSSCs). Among them, the substitution by conducting polymers (CP) has attractedconsiderable attention because of their good stability, high hole-conductivity and simple deposition withinthe mesoporous TiO2 semiconductor. In this thesis work, several s-DSSCs based on CPs used as HTM havebeen developed in order to improve their photovoltaic performances taking into account the following twoobjectives: (i) the optimization of the interfacial charge transfer processes within the solar cell, and (ii) theoptimization of the charge transport within the n-type oxide semiconductor. To reach these goals, eachcomponent that constitutes the device was varied in order to investigate its effect on the device’sperformances. As first attempt, an analytical study is carried out by varying the sensitizer in order todetermine the fragments of the dyes structures, that have an important effect on the in-situ photoelectrochemical polymerization process (PEP) both in organic and in aqueous media and hence on theperformances of the s-DSSCs. Based on these results, a new concept of removing completely the interfacebetween the dye and the HTM is developed. This is achieved by the synthesis of new dyes covalently linkedto an electroactive monomer which is co-polymerized by in-situ PEP. The resulting co-polymer, used asHTM, is covalently linked to the dye. In addition, the nature of the chemical bond linking the triphenylamineresidue TPA to the monomer is also investigated as a key factor in the s-DSSCs performances. Besides, andto optimize the charge transport processes within this type of s-DSSC, the elaboration of novel ZnO baseds-DSSCs has been achieved and investigated
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Emig, Andrew James. "Dye Sensitization in a Photoelectrochemical Water-Splitting Cell Using N,N'-Bis(3-phosphonopropyl)-3,4,9,10-perylenedicarboximide." Youngstown State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1345498406.
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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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Smortsova, Yevheniia. "Dye sensitized solar cells efficiency improvement : optimization of the electrolyte using ionic liquids/molecular solvents mixture and study of the photodynamic properties of organic indolinic derivative dyes." Thesis, Lille 1, 2018. http://www.theses.fr/2018LIL1R061/document.
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Parmi les énergies renouvelables, l’énergie solaire est la plus puissante. L’élément clé des DSSCs est le photosensibiliseur, par lequel la génération de photocourant est possible. L’autre élément important est l’électrolyte. Les liquides ioniques (Ils) sont utilisés en tant qu’électrolytes dans les DSSCs du fait de leurs propriétés chimiques: pression de vapeur basse, haute résistance thermique et chimique, polarité et phase modulables, etc. L’objectif de cette thèse est de comprendre les processus photophysiques dans les colorants dérivés d’indolines dans les solvants moléculaires (MS) et les mélanges IL/MS. L’influence du solvant sur les propriétés spectroscopiques de D131, D102, D149 and D205 est d’abord étudiée par spectroscopie stationnaire d’absorption et de fluorescence. Ensuite, la spectroscopie résolue en temps est employée pour étudier leur photophysique et sa dépendance au solvant. Ces expériences ont permis de démontrer l’influence des paramètres d'aptitude de donneur de liaison hydrogène et d'accepteur de liaison hydrogène des solvants. Le rôle majeur de la dynamique de solvatation dans la dynamique des états excités de ces colorants a été montré. Ce phénomène a été suivi dans les mélanges IL/MS en utilisant une sonde fluorescente classique, C153, et des techniques de fluorescence résolues en temps et de dynamique moléculaire. Les réponses de solvatation multi-régimes de ces mélanges sont dirigées par le renforcement de la liaison hydrogène entre la sonde et les composants des mélanges. Les résultats de cette these apportent beaucoup à la compréhension des processus photophysiques fondamentaux régissant les sensibiliseurs et les électrolytes dans les DSSCsAmong all the renewable energy sources, solar energy is the most powerful source far ahead wind or geothermal energies. The first key component of DSSCs is the photosensitizer. It is through this component that the most important steps of photocurrent generation are possible. On the other hand, ionic liquids (ILs) have been proposed as electrolyte for DSSCs due to their peculiar properties: low vapor pressure, high thermal and chemical robustness, tunability of polarity and phase behaviour etc. The objective of this thesis was to get an understanding of the photophysics in the indoline derivated dyes in molecular solvents (MS) and in the IL/MS mixtures. Firstly, the solvent dependence of the spectroscopic properties of D131, D102, D149 and D205 was studied by the steady-state UV-Vis absorption and fluorescence spectroscopy. Then, time-resolved spectroscopy was used to elucidate their photophysics and its solvent dependence. These experiments helped to discern the influence of the hydrogen bond donor and acceptor abilities of the solvent. The solvation dynamics was shown to play a major role in the excited state dynamics of these dyes. This process in IL/MS mixtures was elucidated using the classic fluorescent probe C153 by the means of time-resolved spectroscopy and MD simulations. The complex multi-regime solvation response in these systems was shown to be shaped by the strengthening of the hydrogen bonding between the probe and the mixture components. The results of this thesis work contribute to the fundamental understanding of the photodynamics of the sensitizer and the response of the electrolyte used in the DSSCs
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Pekkola, René [Verfasser], Wolfram [Akademischer Betreuer] Jaegermann, and Heinz von [Akademischer Betreuer] Seggern. "Electronic Structure of Solid-State Dye-Sensitized Solar Cells: Synchrotron Induced Photoelectron Spectroscopy on Nanocrystalline TiO2, Newly Developed Dyes and Spiro-MeOTAD / René Pekkola. Betreuer: Wolfram Jaegermann ; Heinz von Seggern." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2014. http://d-nb.info/1110792689/34.
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Silva, Maria do Socorro de Paula. "SupressÃo de LuminescÃncia de Corantes CatiÃnicos por Complexo de RutÃnio e sua Potencial AplicaÃÃo em CÃlulas Solares Fotosensibilizadas." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11332.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoComplexos de bipiridinas de rutÃnio sÃo bastante estudados na literatura por apresentarem propriedades de interesse em diversas Ãreas como estudos fotoquÃmicos e fotofÃsicos, aplicaÃÃo em sistemas biolÃgicos e como fotosensibilizadores em cÃlulas solares. No presente trabalho, os complexos do tipo cis-[Ru(bpy)(dcbH2)(L)Cl], onde L = Azul do Nilo (NB), Azul de Toluidina (TBO), 9-Aminoacridina (9AA), Azure B (AB) e Violeta de Cresila (VC) foram sintetizados e caracterizados por tÃcnicas espectroscÃpicas e eletroquÃmica para aplicaÃÃo em cÃlulas solares sensibilizadas por corante (DSCs). AlÃm destes, o complexo cis-[Ru(dcbH2)(bpy)(TCNE)Cl] (Ru-TCNE) tambÃm foi testado como sensibilizador em DSC. Estes compostos apresentaram bandas de transferÃncia de carga do tipo MLCT na regiÃo do visÃvel e potenciais redox termodinamicamente favorÃveis para as reaÃÃes de transferÃncia de carga que ocorrem no dispositivo fotoeletroquÃmico. A adsorÃÃo quÃmica dos complexos sensibilizadores na superfÃcie do TiO2 foi evidenciada pelo deslocamento das bandas de MLCT para regiÃes de menor energia quando comparadas aos espectros em soluÃÃo. Os desempenhos fotovoltaicos dos complexos como sensibilizadores em DSC foram avaliados atravÃs das curvas corrente versus potencial, obtidas em condiÃÃes padrÃo AM 1,5. As DSCs contendo os sensibilizadores Ru-TBO e Ru-AB apresentaram os menores desempenhos fotovoltaicos com eficiÃncia global de 0,02 e 0,06%, respectivamente. JÃ as cÃlulas solares sensibilizadas pelos corantes Ru-NB e Ru-VC obtiveram um rendimento de 0,11% com baixos valores de eficiÃncia de incidÃncia de conversÃo de fÃtons a corrente, IPCE. Os melhores resultados foram para as cÃlulas contendo os corantes Ru-9AA e Ru-TCNE, as quais apresentaram rendimentos de 0,54 e 2,01%, respectivamente, com valores de IPCE iguais a 10% para Ru-9AA e 48% para Ru-TCNE. Todos os complexos apresentaram eficiÃncia global de conversÃo de energia solar em elÃtrica inferiores ao complexo padrÃo N3.
Bipyridines ruthenium complexes are widely studied in the literature for presenting interesting properties in various fields such as photochemical and photophysical studies, applications in biological systems and as photosensitizers in solar cells. In this work, the complexes of the type cis-[Ru(bpy)(dcbH2)(L)Cl], where L = Nile blue (NB), Toluidine blue (TBO), 9-aminoacridine (9AA), Azure B (AB) and Cresyl Violet (VC) were synthesized and characterized by spectroscopic and electrochemical techniques for application in dye-sensitized solar cells (DSC). In addition, the complex cis-[Ru(dcbH2)(bpy)(TCNE)Cl] (Ru-TCNE) was also tested as a sensitizer DSC. These compounds showed bands of charge transfer type MLCT in the visible region and thermodynamically favorable redox potentials for the charge transfer reactions which occur in the photoelectrochemical device. The adsorption of the chemical sensitizers complexes on the surface of TiO2 was evidenced by displacement of MLCT bands to lower-energy when compared to the spectra in solution. The photovoltaic performances of the complexes as sensitizers in DSC were evaluated through current versus potential curves obtained in standard AM 1.5 conditions. The DSC sensitizers containing Ru-TBO and Ru-AB had the lowest overall efficiency with photovoltaic performances of 0.02 and 0.06%, respectively. As for the dye-sensitized solar cells by Ru-NB and Ru-VC obtained a yield of 0.11% with low efficiency values of incident conversion of photon to current, IPCE. The best results were for cells containing the dyes Ru-9AA and Ru-TCNE, with energy conversion efficiency of 0.54 and 2.01%, respectively, with IPCE values equal to 10% for Ru-9AA and 48% for Ru-TCNE moieties. All complexes showed overall efficiency of converting solar energy into electricity below the N3 complex pattern.
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Liu, Yung-Chin, and 劉勇進. "Application and Study of Phthalocyanine and Azo Dyes for Dye-Sensitized Solar Cell." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/85652032548787094481.
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碩士義守大學
生物技術與化學工程研究所碩士班
97
Dye-sensitized solar cells (DSSCs) have been considered as one of the most promising solar cell technologies for their low cost and high efficiency comparable to that of silicon solar cells. The aim of this study is developing efficient and stable DSSCs. We focus on the development of the following two key materials: 1. the organic dyes do not contain noble metals; 2.high specific surface area nanocrystalline TiO2 electrodes. We prepared the DSSCs consisting of mixed phthalocyanine and azo dyes instead of single dye system to utilize the broad spectrum of sunlight. The performances of DSSCs were discussed. The structure, optical and electric properties were characterized by using FT-IR ,UV-vis and CV analysis. Sol-Gel precipitation was applied to make TiO2 thin film electrode. The crystalline phase, grain size and surface morphology of titanium oxide were characterized by using XRD, BET and SEM to investigate the effects of processing parameters on the films characteristic and microstructure. The study also investigated the effect of variable thickness of TiO2 on the efficiency of DSSCs. The AC-impedance analysis of DSSCs show that the performance of DSSCs improved with increasing thickness of TiO2 until 13μm of thickness. At last, We analyzed the performance of DSSCs using IV-curve to get the efficiency of various DSSCs.
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Ting, So-yi, and 丁守儀. "Application and Study of Cyanine and Azo Dyes for Dye-Sensitized Solar Cell." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/65321104153239518066.
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碩士義守大學
生物技術與化學工程研究所碩士班
97
The aim of this study is developing efficient and stable dye sensitized solar cells. We focus on the development of the following two key materials: 1. the organic dyes do not contain noble metals; 2.high specific surface area nanocrystalline TiO2 electrodes. In the part of dyes, we have designed and synthesized the Azo dye having absorption of short wavelength, and mixed it with the Cyanine dye having absorption of long wavelength instead of single dye system to utilize the broad spectrum of sunlight. The performances of DSSCs fabricated in the mixed dyes system were discussed. The adsorption of organic dye on this membrane of TiO2 were characterized by using FT-IR and UV–vis. The optical and electric properties of organic dyes were characterized by using UV-vis and CV analysis. The structure of organic dyes were characterized by using NMR、FT-IR and EA, respectively. In the part of titanium oxide membrane, we apply sol-gel method to make TiO2 membrane electrode. The crystalline phase of TiO2 were characterized by using XRD. The specific surface area and pore size were measured by using BET. The grain size, morphology and thickness of titanium oxide membrane were characterized by using FE-SEM to investigate the effects of processing parameters on the films characteristic and microstructure. The study also investigated the effect of variable thickness of TiO2 on the efficiency of DSSCs. The AC-impedance analysis of DSSCs show that the performance of DSSCs improved with increasing thickness of TiO2 until 10.25μm of thickness. At last, we analyzed the performance of DSSCs by using IV-curve to compare the efficiency of DSSCs contained single dye with the efficiency of DSSCs contain mixed dye.
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黃漢彬. "Dye-Sensitized Solar Cells(DSSC)made with AZO and ITO process and characteristic analysis." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/19041504298467272383.
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碩士中華大學
機械工程學系碩士班
96
Abstract This paper investigates the opto-electric property of the TCO (Transparent Conductive Oxide) films made by ITO and AZO in sputtered on glass. Then analyze the transparent and resistance after annealing the TCO films with different time and temperature to understanding TCO’s characteristic. The final TiO2 film is made by using 7nm TiO2 powder and annealing with 150℃ temperature. The TCO transparency and resistivity was studied first, then the dye-sensitized solar cells power efficiency with graphite anode and added with dye into TiO2 film was also analyzed. The resistivity and transparency at 400nm~700nm of annealed ITO and AZO are measured by KEITHLEY 4200 and spectrophotometer. Finally, the power efficiency of DSSC by using ITO and AZO are measured and compared.
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Huang, Hsin-Hsiang, and 黃信祥. "The effect of AZO and compact TiO2 films on the performance of dye-sensitized solar cells." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/73939000848417307602.
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碩士龍華科技大學
機械工程系碩士班
103
A thin TiO2 compact layers and inexpensive Al2O3-doped zinc oxide (in AZO, the Al2O3 contents are approximately 3 wt.%) transparent conducting films, by means of radio frequency (rf) magnetron sputtering, using deposition parameters that ensure higher photo catalytic activity and increased dye-sensitized solar cells (DSSC) conversion efficiency. Findings based on the grey relational Taguchi method, the lowest electrical resistivity of AZO/glass films to be about 3.4 mΩ-cm, and visible range optical transmittance about 88%. By applying annealing, the AZO films show decreased electrical resistivity due to there is an increase in the Hall mobility and the carrier concentration. With a thin TiO2 compact layer (40, 70, 100 nm) to prevent charge recombination, a higher short circuit current density is obtained. The experimental results show that the DSSC conversion efficiency is critically affected by the thickness of the compact TiO2 layer.
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LEE, ZONG-YAN, and 李宗彥. "Study on AZO/IGZO Transparent Conductive Thin Film for Dye-sensitized Solar Cells with Photoelectric Characteristics and Impedance Analysis under Low Intensity Illumination and Series-parallel Modules." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/remx55.
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碩士國立雲林科技大學
電子工程系
106
In this thesis, the InGaZnO4 (IGZO) film is sputtered on the glass substrate as a buffer layer, and then the Al-doped zinc oxide (AZO) thin film is deposited onto the glass substrate with buffer layer as the transparent conductive oxide (TCO). By using radio frequency (R.F.) sputtering, 4-point probe and alpha-step profiler, the best process parameters are investigated and characterized. The experimental result shows that the optimal electrical resistivity of AZO TCO film is 2.6×10-3 Ω-cm. In addition, the optimal electrical resistivity of AZO/IGZO TCO film, in that the IGZO buffer layer was introduced, decreases to 9.4×10-4 Ω-cm, and the transmittance is over 80% in the visible wavelength range. Then, the dye-sensitized solar cells (DSSCs) are fabricated using the AZO/IGZO TCO glass. The analysis are carried out by using a simulated solar source, quartz filters and electrochemical impedance spectroscopy (EIS). The experimental result shows that the photoelectric conversion efficiency of DSSC with AZO/IGZO TCO film under the illumination of AM 1.5G (100 mW/cm2) is 3.71%, which has a significant improvement when compared to the photoelectric conversion efficiency 3.02% of the DSSC with AZO TCO film. Under the low-intensity illumination of 1.75 mW/cm2 (T5), the photoelectric conversion efficiency of AZO/IGZO DSSC is up to 6.89%. For practical applications, the DSSCs are further fabricated in the forms of series and parallel modules. The resultant DSSCs modules were analyzed to measure the change of current and voltage by using EIS and solar simulator.
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Lai, Xuan-Rong, and 賴宣融. "Development of natural dyes for dye sensitized solar cells." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/wkt9nv.
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碩士國立臺北科技大學
機電整合研究所
100
The performance of dye sensitized solar cells is mainly based on the dye as a sensitizer, the natural dyes have extensively replaced synthetic dyes. In the experiments of the research is based on the two natural dyes of chlorophyll and anthocyanin for the study, one of the natural dyes is chlorophyll, which is extracted from wormwood and the other is anthocyanin dye which is extracted from purple cabbage extract. In addition, the chlorophyll and anthocyanin dyes were blended in the proportion of equal volume as cocktail-form dyes. The way of extracting natural dye is to mix the materials in a container of absolute ethanol, methanol and acetone, which is then placed in another container of water for heating and the temperature of heating is 50oC for 30 min, so as to extract dye. Regarding the preparation of electrode for experiments of the study, P25 TiO2 powder for commercial use is coated by Spin coating on the ITO conducting surface to form a thin film. The FTO for use by electrode is Pt electrode at thickness of around 20nm made by sputtering. Each of the dyes absorbs spectrum UV-VIS. The absorption peak of chlorophyll dye is 660 and 410 nm, whereas the absorption peak of anthocyanin dye is 550 nm. But cocktail dye can acquire the absorption features of both dyes, with absorption strength being within the range of absorption strength of these two independent dyes. the photoanode was made by spin coasting, preparation of films have been made at three different speeds 500 1000 1500 rpm, approximately 30, 25 and 20 μm. The result of experiment shown that the film is made at speed 1000rpm with the cocktail dissolve in solvent of absolute ethanol achieve the greatest photo-electric conversion effciency (η) 1.74%, open-circuit voltage (VOC) 0.645V, and short-circuit current density (JSC) 3.16mA/cm2. In addition the chlorophyll dye is extracted from wormwood achieves the photo-electric conversion efficiency (η) 0.9%, moreover the anthocyanin dyes extracted from purple cabbage achieves the photo-electric conversion efficiency 1.47%.
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Lo, Yu-Jen, and 羅右任. "Natural Dyes as Photosensitizers for Dye-sensitized Solar Cells." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/6597yz.
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碩士國立臺北科技大學
製造科技研究所
97
In this paper, we have extracted chlorophyll from the pomegranate leaves and anthocyanin from mulberry fruits to used as-prepared natural dye to investigate the correlation between the extraction solvent and the extraction temperature and the concentration and pH condition for dye extraction to DSSC performance. Then combine chlorophyll and anthocyanin as the dye cocktails to perform the photoelectron conversion efficiency.In addition, Electrophoretic deposition was performed to let the TiO2 deposite nanoparticles on the indium tin oxide (ITO) conductive glass, forming a TiO2 thin film with the thickness of 10~13 μm. This TiO2 thin film underwent sintering at 450℃ to enhance the compactness of thin film. Counter electrode is sputtered prepared 20 nm Pt film on FTO glass. The electrodes, electrolyte (I3-), and dyes were assembled into a cell module and illuminated by light source of simulate AM1.5 with light strength of 100 mW/cm2 to perform the photoelectron conversion efficiency test. The result showed the efficiency of 0.597 % for chlorophyll with open-circle voltage (VOC) of 0.56 V and short-circuits current density (JSC) of 2.05 mA/cm2, and fill factor (FF) of 0.52. The efficiency of 0.548 % for anthocyanin with open-circle voltage (VOC) of 0.555 V and short-circuits current density (JSC) of 1.89 mA/cm2, and fill factor (FF) of 0.53. The efficiency of 0.722 % for chlorophyll and anthocyanin as the dye cocktails with open-circle voltage (VOC) of 0.53 V and short-circuits current density (JSC) of 2.8 mA/cm2, and fill factor (FF) of 0.49.
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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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SU, TING-YI, and 蘇亭伊. "The Study of Dye-sensitized Solar Cells with Compound Dyes." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/4g8q85.
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碩士國立高雄應用科技大學
光電與通訊工程研究所
105
In this study, the proposed dye-sensitized solar cells use two different types of dyes as the sensitizers of the cells. This co-sensitization can improve the ability of light capture and the conversion efficiency of the cell because each dye has its own absorption spectrum which can be arranged complementary to the other dye. In fact, the co-sensitization technique makes a broader absorption of solar energy to improve the performance of the cell. In this study, N719 and SQ2 are used as the sensitizers of the proposed dye-sensitized solar cells. An ultrasonic treatment is employed during the immersion of the titanium dioxide layer into the dye solution to dramatically reduce the process time, from typically 8-24 hours of immersion down to about 20 minutes. A cocktail approach and a stepwise approach are used to evaluate the performance of the resultant cells. The cocktail approach is studied to understand how the mixture of N719 and SQ2 dyes in different volume ratios affects the conversion efficiencies of the cells. The optimal conversion efficiency of 4.65% is found for the cell sensitized with the co-sensitizer (N719+SQ2) at the volume ratio of 6:4, which is higher than that of 3.7% for the cell sensitized with N719 dye and that of 0.92% for the cell sensitized with SQ2 dye. The stepwise approach is studied to understand how the dyeing of N719 and SQ2 in the time sequence on the titanium dioxide layer affects the conversion efficiencies of the cells. The optimization of the time interval for dyeing N719 and SQ2 sequentially on the titanium dioxide layer and the period of time for ultrasonic treatment is included in this study. In the case of dyeing N719 and then SQ2, each under ultrasonic treatment for 10 minutes, the results show that the optimal conversion efficiency of the cell is 2.91%. On the other hand, in the case of dyeing SQ2 and then N719, the conversion efficiency is lower, which is 2.55%. However, when the titanium dioxide film is sequentially immersed in N719 solution for 20 minutes and SQ2 solution for 5 minutes with ultrasonic treatment, the optimal conversion efficiency of the cell is up to 4.32%
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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.
Full textAbstract:
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.
Full textAbstract:
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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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.
Full textAbstract:
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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Anwar, Hafeez. "Precious Metal-free Dye-sensitized Solar Cells." 2013. http://hdl.handle.net/10222/42686.
Full textAbstract:
Exploring new technologies that can meet the world’s energy demands in an efficient and clean manner is critically important due to the depletion of natural resources and environmental concerns. Dye-sensitized solar cells (DSSCs) are low-cost and clean technology options that use solar energy efficiently and are being intensively studied. How to further reduce the cost of this technology while enhancing device performance is one of the demanding issues for large scale application and commercialization of DSSCs. In this research dissertation, four main contributions are made in this regard with the motivation to reduce further cost of DSSC technology. Firstly, ~10% efficiencies were achieved after developing understanding of key concepts and procedures involved in DSSCs fabrication. These efficiencies were achieved after step-by-step modifications in the DSSC design. Secondly, carbon nanotubes (CNTs) were successfully employed as an alternative to Pt in the counter electrodes of DSSCs. DSSCs fabricated with CNTs were ~86% as efficient as Pt-based cells. Non-aligned CNTs were successfully grown using four different CVD methods and finally, multi-walled vertically aligned CNTs (MW-VACNTs) were synthesized using water-assisted chemical vapor deposition (WA-CVD). Thirdly, carbon derived from pyrolysis of nanocrystalline cellulose (NCC) was successfully employed in counter electrodes of DSSCs instead of Pt. DSSCs with NCC were ~58% as efficient as Pt-based DSSCs. Fourthly, novel organic metal-free dyes were designed and employed instead of commonly used Ru-based dyes. DSSCs with these novel sensitizers were ~62% as efficient as those using the conventional Ru-based dyes. Characterization techniques including current-voltage measurements, scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), cyclic voltammetery (CV), thermogravimetric analysis (TGA), small angle x-ray scattering (SAXS), atomic force microscopy (AFM) and x-ray photoelectron spectroscopy (XPS) were used.
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Zeng, Guang-Rong, and 曾光榮. "Study on Cosensitized by Organic Dyes for Dye Sensitized Solar Cells." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/10533086598278530529.
Full textAbstract:
碩士明志科技大學
化工與材料工程研究所
99
The metal-free organic dyes: coumarin 343(C343), Eosin Y(EoY), fluorescein(F), fluorescein isothiocyanate(FNCS) and Rhodamine B (Rho B) are used to sensitize nanocrystalline porous TiO2 films and applied for dye-sensitized solar cells (DSSCs). J-V curve measurements show the DSSC based on Eosin Y receives the best photoelectric conversion efficiency with 0.473%. The dyes loading of the photoelectrodes were measured by dye-desorption experiments and indicates that the C343 dye has best adsorption ability and TiO2 photoelectrode get a highest loading of 15.8×10-8 mol/cm2. We use six binary systems (C343/EoY, C343/F, C343/FNCS, EoY/C343, EoY/F and EoY/FNCS) employed as sensitizers to study cosensitization in the DSSCs. By analysis of J-V curve, IPCE and EIS measurements, the results exhibit that the EoY/F binary system has the best performance on extension of the absorption range of the nanocrystalline photovoltaic cell, reduction of the electron recombination at the photoelectrode/electrolyte interface, and increase of the photoelectric conversion efficiency.
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TANG, DONG-LIN, and 湯東霖. "The Application of New Organic Dyes for Dye Sensitized Solar Cells." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/xpv74a.
Full textAbstract:
碩士國立聯合大學
光電工程學系碩士班
106
This study demonstrated the new organic materials served as the absorption layer in dye-sensitized solar cells (DSSC). we prepared three phenothiazine (PTA)-based D-π-A organic dyes (TC6PTA, TBOC6PTA, and cC6PTA). We designed TC6PTA with triphenylamine as the basic donor unit, then changed the conjugated moiety on the PTA bridged unit, named TBOC6PTA. In addtion, the planarity donor (carbazole) unit was used to replace the triphenylamine, named cC6PTA. Their optical properties were studied and their practical application in dye-sensitized solar cells was demonstrated. All three dyes had the best power conversion efficiency (PCE) at 0.2 mM , TC6PTA was 6.61%, TBOC6PTA was 6.02%, and cC6PTA was 6.92%. In addition, the solvent effect also affect power conversion efficiency. The results show that TC6PTA has a power conversion efficiency of 6.48% when ethanol is a solvent, the PCE is 6.89% when TBOC6PTA is dissolved in acetonitrile, and when cC6PTA is dissolved in ethanol, the PCE of 6.92% is achieved. We could observed that the device efficiency can be effect by the dye molecule design, different concentration and solvent effect. The molecule design can be optimized by replacing the electron donor unit and the coplanar moiety. The device efficiency could be compared with N719 dye by using suitable concentration and solvent.
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Chou, Yun Yi, and 周昀毅. "Utilization of Nature Dyes as Photosensitizers for Dye-sensitized Solar Cells." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/u2r7dy.
Full textAbstract:
碩士國立臺北科技大學
有機高分子研究所
96
Since 1991, Grätzel et al. have developed the first dye-sensitized solar cells (DSSC), it has been studied extensively. Ru transition-metal complexes (N3, N719) were the most commonly used dye to achieve high cell efficiency up to 11%. The commercial Ru-dyes are, however, very expensive. In this experiment, we have extracted anthocyanins from the red cabbage and xanthophylls from yellow chrysanthemum to used as-prepared natural dye to investigate the correlation between the extraction solvent and the concentration and pH condition for dye extraction to DSSC performance. Then combine anthocyanins and xanthophylls as the dye to perform the photoelectron conversion efficiency. The working electrode was made of nanocrystalline TiO2 paste prepared by mixing the Degussa TiO2 (DP-25) with acetylacetone, triton X-100, and DI water. The TiO2 paste was uniformly dispersed on the FTO glass and calcined at 450 °C to form the final TiO2 electrode. Counter electrode is sputtered prepared 20 nm Pt film on FTO glass. The electrodes, electrolyte (I3‾), and dyes were assembled into a cell module and illuminated by light source of simulate AM1.5 with light strength of 100 mW/cm2 to perform the photoelectron conversion efficiency test. The result showed the efficiency of 0.581 % for anthocyanins with open-circle voltage (VOC) of 0.55 V and short-circuits current density (JSC) of 1.60 mA/cm2, and fill factor (FF) of 0.59. The efficiency of 0.626 % for xanthophylls with open-circle voltage (VOC) of 0.58 V and short-circuits current density (JSC) of 1.68 mA/cm2, and fill factor (FF) of 0.640. The efficiency of 0.747 % for anthocyanins and xanthophylls as the dye with open-circle voltage (VOC) of 0.62 V and short-circuits current density (JSC) of 1.76 mA/cm2, and fill factor (FF) of 0.684.
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Lin, Yeo-Sin, and 林佑昕. "Dipolar Organic Dyes Containing 1,3-Cyclohexadiene for Dye-Sensitized Solar Cells." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/85942905333942830233.
Full textAbstract:
碩士國立臺灣師範大學
化學系
101
Three new organic dipolar D-π-A dyes（DM132, DM141, DM157）with triarylamine as the electron donor, carboxylic acid or cyanoacrylic acid as an electron acceptor as well as an anchoring group, connected with thieno[3,2-b]thiophene and a π-conjugated spacer 1,3-cyclohexdiene or phenyl between the electron donor and acceptor. The photophysical and electrochemical properties of the three dyes were studied in details by UV/ Vis, fluorescence spectroscopy, and cyclic voltammetry. The cell performances of cells assembled from these light-harvesting dyes have been evaluated using the AM 1.5 simulated solar light. The results showed that DM141 has the best power conversion efficiency of 2.86 %（Jsc = 7.63 mA/cm2, Voc = 608 mV, ff = 0.62）under AM 1.5 irradiation（100 mW/cm2）whereas DM132（η= 1.37%）with 1,3-cyclohexdiene moiety within the π-framework was not as effective as expected perhaps due to non-effective charge separation, fast charge recombination and aggregation, which leads a low overall efficiency. A general correlation between the structural factors and the cell performances are currently under investigation aiming to provide a guideline for future design of high performance light-harvesting dyes.
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Lin, Tsu-han, and 林祖涵. "Synthesis of Unsymmetrical Near-IR Dyes for Dye-Sensitized Solar Cells." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/63535224707542129743.
Full textAbstract:
碩士國立中央大學
化學研究所
98
Solar energy is one of the most promising energy resources due to its cleanliness and abundance. Amongst the newly developed photovoltaic technologies to convert sunlight to electricity, Dye-sensitized solar cells (DSCs) have attracted significant attention as one of the low-cost alternatives for the realistic applications due to their impressive conversion efficiency. Numerous metal-free organic dyes with high molar extinction coefficients have been developed. Nevertheless, there are few dyes which can efficiently absorb the far-red and near-IR lights. In this thesis we synthesize a series of unsymmetrical squaraine photo-sensitizer: JYL-SQ1, JYL-SQ2, and THL-SQ3. These squaraine sensitizers contain a donor group (such as thiopene or carbazole), a conjugate moiety (squaraine) and an acceptor group (indoline with COOH). The carbazole-containing sensitizers show widely absorption bands and the absorption maximum (λmax) of THL-SQ3 is slightly red shifted to 612 nm compared to JYL-SQ1 and JYL-SQ2 (with an absorption maximum at 603 nm and 568 nm, respectively). Furthermore, the corresponding molar absorption coefficient (ε) of THL-SQ3 (134151 M-1 cm-1) is higher than those for JYL-SQ1 (85791 M-1 cm-1) and JYL-SQ2 (68694 M-1 cm-1). The overall conversion efficiency (η) for JYL-SQ2 was 2.59 %, which is 60 % of the N719 based device (4.40 %) fabricated at the same condition. The data reveal that such type of molecular design has great potential to prepare high efficiency sensitizers for dye sensitized solar cells.
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Chen, Chih-Han, and 陳致翰. "New Device Structures and Novel Organic Dyes for Dye-Sensitized Solar Cells." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/41118123504076654458.
Full textAbstract:
碩士國立東華大學
光電工程學系
102
Abstract The advantages of dye-sensitized solar cells (DSSCs) are easy manufacturing, low cost, and high power efficiency. Typically, a dye-sensitized solar cell is composed of five major parts, which include transparent conductive substrate, titanium dioxide, dye, electrolyte, and platinum. In recent years, the issue of energy supply shortage has increased the research speed of dye-sensitized solar cells. In this thesis, we first studied three kinds of organic dyes and investigated the characteristics of dye-sensitized solar cells using these organic dyes. We studied the current-voltage curve, impedance spectroscopy, external quantum efficiency, electron lifetime, electron transport time, and charge collection efficiency. We also investigated the behavior of electron in dye-sensitized solar cell using these novel organic dyes. Second, we investigated the efficiency of heterojunction solar cells which was composed of cuprous oxide and electrolyte. We used the chemical oxidation method to fabricate the coral structure cuprous oxide on copper substrates. The surface morphology of the cuprous oxide was observed using electron microscope. The internal elements ratios were observed by X-ray diffraction, Raman measurement, and X-ray photoelectron spectroscopy. Finally, the characteristics of Cu2O/electrolyte heretrojunction solar cell were studied. This research investigated the relevance between the iodine concentration and device efficiency. Finally, we used the graphene nanosheets combining with platinum as the couner electrodes to improve the catalytic property of counter electrodes. We first used the Raman measurement to identify the quality of graphene nanosheets and X-ray photoelectron spectroscopy to study the elements and internal defects. Then atomic force microscopy and cyclic voltammetry were used to observe the surface roughness and catalytic activity. Finally, we investigated the efficiency, external quantum efficiency, and impedance spectroscopy of the DSSCs using graphene nanosheets combining wth platinum as counter electrodes.
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Hsueh, Wei-tsung, and 薛惟聰. "New CPDT Containing Donor-Acceptor Organic Dyes for Dye-Sensitized Solar Cells." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/02611628063574636256.
Full textAbstract:
碩士國立中央大學
化學研究所
96
The advantages of metal free sensitizers, compared to the Ru-based sensitizer in the Grätzel cell, are the high absorption coefficient and without using expensive metal. Furthermore, the structure of organic sensitizers can be widely modified to enhance the performance for solar cells. In general, the organic sensitizer contains a Donor group (such as Carbazole or Triphenylamine), a Spacer and Acceptor group (CN with COOH) to form so called Donor-Spacer-Acceptor type dyes. We synthesize a series organic dyes containing N-arylcarbazole or Triphenylamine as donor group and cyano arylic acid as a Acceptor, a low band gap CPDT moiety with thiophene, bithiophene, or octylthiophene, respectively as a Spacer. Dye-sensitize Solar Cells (DSCs) based on these dyes were fabricated and their performance was test to reveal the relationship between the structure of the dye and the performance of the DSC based on it. It was found that dye using N-aryl Carbazole as a Donor and CPDT-bithiophene as a Spacer has the highest conversion efficiency of 1.78%. Several parameters will affect the performance of dye for solar cell, such as ?max, distribution of HOMO and LUMO, and molecular dihedral angle. Nevertheless, it seems that the absorption coefficient of the dye did not have a significant effect on the conversion efficiency of the DSC based on it。
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Hsieh, Wei-Szu, and 謝維斯. "Synthesis of Novel Triphenylamine Derivative Organic Dyes for Dye-Sensitized Solar Cells." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/2m497d.
Full textAbstract:
碩士國立臺北科技大學
有機高分子研究所
98
In this thesis,we have successfully synthesized a series of triphenylamine derivative dye compounds, their structures contain electron-donating groups, π bridges, modified groups and electron-accepting groups, this chapter mainly discusses the different π bridges、 modified groups and electron-accepting groups of its photoelectric conversion efficiency.π bridges with thiophene and 3,4-Ethylenedioxythiophene as a π-conjugated connection chain, modified groups design modification of thiophene as the main group, and joined the alkyl chain to increase solubility, to facilitate the production of solar cell components, and because alkyl chain has a hydrophobic nature, the introduction of hydrophobic groups can reduce the dye caused by water desorption of the case. Use cyanoacetic acid、rhodanine-3-acetic acid and malonic acid as the electron-accepting groups . All of these compounds were characterized by UV/VIS spectrophotometer, fluorescence spectrophotometer and cyclic voltammetry.Also be made into dye-sensitized solar cell components, The power-conversion efficiency was measured by the AM1.5 simulated solar light system.