Thesis (Ph. D.)--University of Idaho, 2005. / Also available online in PDF format. Abstract. "July 2005." Includes bibliographical references.

The depletion of fossil fuels and the increasing energy demand for energy has led to the search for better and improved technologies with special focus renewable energy, especially solar cells. The first generation solar cells based on silicon are expensive, hence dye sensitized solar cells come in as a better alternative as these solar cells are environmental friendly, they have moderately good conversion efficiency and they are relatively cheap to produce. Dithiocarbamate ligands have been widely used in many research fields, as these are versatile ligands. Coordination of dithiocarbamates with metals such as ruthenium has produced high conversion efficiency and have the ability to extend the MLCT absorptions, and this can further extend their wavelength. In this study five dithiocarbamate sodium salt ligands were prepared and were coded as FL1= Aniline, FL2= p- toluidine, FL3= p- anisidine, FL4=dibenzyl, FL5=diphenyl. These ligands were used to synthesize Ru(II) metal complexes which were formulated as [Ru(FLx)(dcbpy)(NCS)] and [Ru(FLx)2(dcbpy)] where FLx is the dithiocarbamate ligand and dcbpy is 2,2-bipyridine-4,4’-dicarboxylic acid and the complexes were coded as FCx. The synthesized compounds were characterized using techniques such as the melting point, molar conductivity, FT-IR and NMR spectroscopy. For spectroelectrochemical studies of the metal complexes, techniques such as UV-Vis and photoluminescence spectroscopy were carried out. Furthermore, redox properties of the complexes were analyzed using cyclic and square wave voltammetry. The FT-IR displayed all the expected peaks of interest both in the dithiocarbamate ligands and in the metal complexes. The electronic spectra confirmed the successful coordination of ligand to the metal centre, the electronic spectra of the complexes also confirmed the six coordinate octahedral geometry of the complexes. The complexes exhibited some photoluminescence properties that are suitable for dye sensitization. The cyclic voltammogram of the complexes displayed more reduction potentials that could be attributed to the π-conjugation in the ligands incorporated during synthesis. The square wave voltammogram of the complexes is in agreement with the results obtained in cyclic voltammetry.

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

This thesis describes the synthesis and characterization of a series of photosensitizers, transition metal-containing polymers and small organic molecules for dye-sensitized solar cells and organic solar cells. To begin with, a brief overview on the background of dye-sensitized solar cells (DSSCs) and organic solar cells was presented in Chapter 1. In Chapter 2, a series of novel donor-acceptor-π-acceptor bithiazole-based and fluorenone-based organic dyes for dye-sensitized solar cells were successfully synthesized and fully characterized. We discovered that the performance of the photovoltaic devices depends significantly on the nature and strength of the electron-donating end group along the conjugated main. Some of the materials have been found to show higher power conversion efficiency of 4.71% (Voc = 565 mV, Jsc = 11.71 mA cm–2, FF = 0.71) under AM 1.5 irradiation (100 mW cm–2). In Chapter 3, ten novel donor-donor-π-acceptor organic dyes for dye-sensitized solar cells have been synthesized and applied for the fabrication of DSSCs, including six dibenzothiophene-based photosensitizers and carbazole-based photosensitizers. All the dyes have efficient charge injection from the excited sensitizer molecule to TiO2 conduction band and can provide ample driving force for efficient dye regeneration best overall light to electricity conversion efficiency of 5.28% (Voc = 0.70 V, Jsc = 11.06 mA cm–2, FF = 0.68) under AM 1.5 irradiation, which reached 73% with respect to that of an N719-based device fabricated under similar fabrication conditions. Besides, nine novel di-anchoring organic sensitizers employing two different electron-donating cores, which are the fluorene and carbazole units, and two symmetrical anchoring cyanoacrylic acid (acceptor) termini have been synthesized and studied for their applications in DSSCs in Chapter 4. In Chapter 5, four new platinum polyyne polymers were prepared via the Sonogashira-type dehydrohalogenation reaction between the ethynyl precursor and trans-Pt(PBu3)2Cl2. All of the polymers are air-stable and well characterized by different spectroscopic methods and photophysical measurements. Their photovoltaic behaviors were fully investigated. Their model compounds were also prepared and studied. In Chapter 6, a series of new organic small molecules were designed and synthesized comprising head-to-head coupled heylthiophene, dithienosilole and dithienogermole units. They exhibited broad absorption peaks with favorable spectral overlap with the solar spectrum. These seven small molecules have been applied to presented. Among these molecules, the highest PCE of 4.93% was achieved with a Voc = 0.79 V, Jsc = 1.22 mA cm-2 and FF = 0.51 under illumination of an AM 1.5 solar cell simulator. Finally, Chapters 7 and 8 present the concluding remarks and the experimental details of the work described in Chapters 2−6

La première partie de ce travail est consacrée à l’évaluation de l’efficacité photocatalytique de plusieurs semiconducteurs commerciaux. La comparaison est basée sur la détermination de leurs propriétés physiques : diamètre des particules, taille des cristallites, structure cristallographique, propriétés électroniques, composition chimique ainsi que capacité d’adsorption. L’efficacité photocatalytique est testée sur le phénol, un polluant modèle. Alors que ZnO présente une activité photocatalytique légèrement supérieure à celle des différents TiO2 étudiés, c’est pour le TiO2 P25 que la plus faible résistivité a été observée. C’est donc au sein de ce dernier que la circulation électronique est la meilleure. L’existence de différentes formes cristallographiques pour le TiO2 est démontrée être également un autre paramètre fondamental gouvernant la réactivité. Si la partition anatase/rutile (80/20%) est donc importante, le fait que le TiO2-P25 soit formé d'un seul cristallite le semble tout autant, car c’est tout le grain qui peut être considéré comme actif.Une seconde partie est dédiée à l’étude de la dégradation photocatalytique d’un colorant, le Vert Cibacron (RG12) utilisé dans l’industrie textile. Le travail est réalisé en suspension aqueuse en présence de dioxyde de titane TiO2-P25. La décoloration de la suspension est effective après 90min de traitement et s’accompagne d’une minéralisation partielle de 60% pour une gamme de concentration initiale en RG12 entre 10-40 mgL-1. Pour déterminer le mécanisme général de la photocatalyse, des investigations thermodynamiques et cinétiques ont été menées sur l’adsorption du colorant sur TiO2-P25. La chimisorption s’est avérée être le processus spontané endothermique majoritaire se déroulant à la surface du photocatalyseur. La cinétique d’adsorption suit globalement une loi de pseudo-ordre deux accompagnée d’un mécanisme de diffusion intraparticulaire observé aux fortes concentrations (80-120 mgL-1) mettant en avant les mésopores du matériau. Un modèle faisant intervenir une adsorption compétitive des espèces à la surface du photocatalyseur a été élaboré. Les molécules de colorant, de sous-produits de dégradation, les molécules d’eau et ions hydroxydes, ainsi que le dioxygène présent en solution et à la surface du TiO2 sont supposés entrer en compétition vis à vis des mêmes sites d’adsorption. Il est alors observé que l’inverse de la constante de dégradation photocatalytique du colorant dépend d’un polynôme du second degré de la concentration initiale du colorant de départ.Afin de contrecarrer le problème récurrent de la filtration des suspensions aqueuses de TiO2, la fixation de TiO2 par la méthode PMTP sur des plaques de verre a été étudiée. La caractérisation des dépôts par MEB et DRX a permis de montrer que ceux-ci étaient homogènes. Les performances du TiO2 supporté ont été comparées au procédé photocatalytique classique en suspension aqueuse sur le colorant Vert Cibacron dans un réacteur à recirculation de 500 mL dont les conditions optimales de fonctionnement ont été déterminées. Le modèle précédent de compétition d’adsorption des espèces à la surface du photocatalyseur, s’est montré adapté à décrire les résultats expérimentaux comparativement au modèle de Langmuir-Hinshelwood.Enfin, le couplage photocatalyse/sonolyse a été examiné pour la dégradation du vert Cibacron. Le dosage des espèces actives générées par chaque technique a été réalisé. Une synergie est apparue lors du couplage de la photocatalyse sous irradiation solaire en présence d’ultrasons 500 kHz. / The first part of this work is dedicated to the evaluation of the photocatalytic efficiency of semiconductors ZnO, TiO2 P25, and two other titanium dioxides (anatase 100%). The comparison was based on determining the physical properties of photocatalysts, mainly: the particle diameter, crystallite size, crystallographic structure, electronic properties, chemical composition and the adsorption capacity. The photocatalytic efficiency was tested with phenol as target molecule. While comparable photocatalytic activity was found with ZnO and TiO2 P25, the lowest resistivity was observed with TiO2 P25, which means that a better electronic circulation occurs in this last photocatalyst compared to ZnO, but also that there is another fundamental parameter governing the reactivity. Under the same crystallographic form, 100% anatase, the photoreactivity of TiO2 is slightly higher with the photocatalyst having the lowest grain's diameter. The highest photoreactivity of TiO2 P25 can be explained by the partition anatase/rutile (80/20%), a higher electronic circulation and by the fact that TiO2 P25 is formed from a single crystallite, where any grains are considered as photoactive. Second part concerns the photocatalytic degradation of dye Cibacron Green (RG12) used by textile industry, in aqueous suspension in the presence of titanium dioxide TiO2 P25. Discoloration of the suspension was effective after 90min treatment with a partial mineralization 60% of the initial dye (10-40 mgL-1). To determine the general mechanism of the photocatalytic process, especially if the surface of the material is involved or not, thermodynamic and kinetic investigations were investiagted on adsorption. Chemisorption was found to be the majority endothermic spontaneous process occurring on the surface of the photocatalyst. Moreover, the adsorption kinetics follows a pseudo-second order law with a intraparticle diffusion mechanism which was observed at higher concentrations (80-120 mgL-1) highlighting the mesopores of TiO2. As the Langmuir-Hinshelwood, Ollis and Direct –Indirect models were enable to fully describe our experimental results, a new model involving a competitive adsorption of species on the surface of the photocatalyst was developed. Dye molecules, byproducts of degradation, water molecules, hydroxide ions and the oxygen present in solution are assumed to compete with respect to the same sites of adsorption at the TiO2 surface. The model showed that the inverse of the constant of the dye photocatalytic degradation depended on a second degree polynomial of the initial concentration of initial dye. Binding experiments of TiO2 on glass plates by the method PMTP were carried out in order to work with supported TiO2 in a dedicated reactor having a recirculation of 0.5 L and where optimum operating conditions were determined. Characterization of deposits by SEM and XRD showed that they were homogeneous with a density of 0.26 mg TiO2/cm². Performances of the supported TiO2 were compared to the conventional photocatalytic process in aqueous suspension by studying the discoloration of the previous dye Cibacron green. The competitive adsorption model elaborated well described experimental results. Final examination was done by coupling photocatalysis and sonolysis for the degradation of Cibacron Green. The determination of the active species generated by each technique was performed. A synergy was observed under solar irradiation of TiO2 in the presence of 500 kHz ultrasound which could provide from an extensive mass transfer of the dye on the photocatalyst induced by ultrasounds.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-04-10T14:03:59Z No. of bitstreams: 0 / Made available in DSpace on 2015-04-10T14:03:59Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

abstract: Dye sensitized solar cells (DSSCs) are currently being explored as a cheaper alternative to the more common silicon (Si) solar cell technology. In addition to the cost advantages, DSSCs show good performance in low light conditions and are not sensitive to varying angles of incident light like traditional Si cells. One of the major challenges facing DSSCs is loss of the liquid electrolyte, through evaporation or leakage, which lowers stability and leads to increased degradation. Current research with solid-state and quasi-solid DSSCs has shown success regarding a reduction of electrolyte loss, but at a cost of lower conversion efficiency output. The research work presented in this paper focuses on the effects of using nanoclay material as a gelator in the electrolyte of the DSSC. The data showed that the quasi-solid cells are more stable than their liquid electrolyte counterparts, and achieved equal or better I-V characteristics. The quasi-solid cells were fabricated with a gel electrolyte that was prepared by adding 7 wt% of Nanoclay, Nanomer® (1.31PS, montmorillonite clay surface modified with 15-35% octadecylamine and 0.5-5 wt% aminopropyltriethoxysilane, Aldrich) to the iodide/triiodide liquid electrolyte, (Iodolyte AN-50, Solaronix). Various gel concentrations were tested in order to find the optimal ratio of nanoclay to liquid. The gel electrolyte made with 7 wt% nanoclay was more viscous, but still thin enough to allow injection with a standard syringe. Batches of cells were fabricated with both liquid and gel electrolyte and were evaluated at STC conditions (25°C, 100 mW/cm2) over time. The gel cells achieved efficiencies as high as 9.18% compared to 9.65% achieved by the liquid cells. After 10 days, the liquid cell decreased to 1.75%, less than 20% of its maximum efficiency. By contrast, the gel cell's efficiency increased for two weeks, and did not decrease to 20% of maximum efficiency until 45 days. After several measurements, the liquid cells showed visible signs of leakage through the sealant, whereas the gel cells did not. This resistance to leakage likely contributed to the improved performance of the quasi-solid cells over time, and is a significant advantage over liquid electrolyte DSSCs. / Dissertation/Thesis / M.S.Tech Engineering 2012

nÃo hà / In this work was carried out an extensive investigation of the adsorption properties of synthetic dyes on different parts (rhizome, root, stolon and petiole) of Eichhornia crassipes (water hyacinth) and a comparison with the adsorption capacity of the biopolymer alginate beads doped with water hyacinth biomass. The biomasses and spheres were structurally characterized by infrared spectroscopy, scanning electron microscopy - SEM and thermal analysis (thermogravimetric analysis - TGA and Differential Scanning Calorimetry - DSC). The kinetics of adsorption processes were monitored by UV and visible spectroscopy - UV / VIS and the data applied to the models of Freundlich and Languimir. Synthetic anionic dyes (methyl orange), cationic (methylene blue) and azo (indigo carmine) were used in the investigation. Adsorption studies was obtained, under controlled agitation of 70 rpm and temperature ranging between 25ÂC and 45ÂC at concentrations of dye in the range 10-250 mg/L and pH 2-12. The best results were achieved with a dye initial concentration of 100 mg/g, an initial quantity of 60 mg biosorbent, at temperature of 45 ÂC and at basic pH. Among the tested dyes, methylene blue exhibited the best adsorption capacity. The study of adsorption kinetics showed a better fit to the model of pseudo-second order and intraparticle diffusion is involved in the mechanism of adsorption. In the study of the isotherms, the result shows best fit to data by the Langmuir and Freundlich equations, with a maximum capacity of adsorption of methylene blue dye from 819.7 mg/g at 25 ÂC, to the root. A temperature increase caused an increase in system adsorption capacity and also led to an increase in time to the system reach equilibrium. The values of the rate constant for pseudo-second order increased with increasing temperature. An increase in initial dye concentration caused an increase in the amount of dye adsorbed. The activation energy for all biosorbents are in the range 20-40 kJ.mol-1 demonstrated that the adsorption processes are physical. The thermodynamic parameters ∆HÂ, ∆S and ΔGÂ, for most biosorbents indicate that the process is exothermic in nature, spontaneous and favorable, except for the sphere of ALG/GC/Biomass where values obtained showed endothermic nature. The desorption study showed that the biosorbents can be reused. / Neste trabalho foi realizada uma investigaÃÃo extensiva das propriedades de adsorÃÃo do corante azul de metileno em diferentes partes (rizoma, raiz, estolÃo e pecÃolo) de Eichhornia Crassipes (aguapÃ), bem como uma comparaÃÃo com a adsorÃÃo em esferas do biopolÃmero alginato dopadas com biomassa de aguapÃ. As biomassas e esferas foram caracterizadas estruturalmente atravÃs de tÃcnicas de espectroscopia de infravermelho, microscopia eletrÃnica de varredura â MEV e anÃlises tÃrmicas (anÃlise termogravimÃtrica â TGA e Calorimetria Diferencial de Varredura â DSC). As cinÃticas dos processos de adsorÃÃo foram monitoradas por espectroscopia de ultravioleta e visÃvel â UV/VIS e os dados obtidos aplicados nos modelos de Languimir, Freundlich, Temkin e BET. Foram utilizados corantes sintÃticos aniÃnico (alaranjado de metila), catiÃnico (azul de metileno) e azo (Ãndigo carmin). Os estudos de adsorÃÃo foram obtidos, sob agitaÃÃo controlada de 70 rpm e temperatura variando entre 25ÂC e 45ÂC, e concentraÃÃes de corante na faixa de 10 a 250 mg/L, em pH de 2 a 12. Os melhores resultados foram alcanÃados utilizando uma concentraÃÃo inicial de corante de 100 mg/g, uma massa inicial de biosorvente de 60 mg a temperatura de 45 ÂC e em pH bÃsico. Dentre os corantes testados o azul de metileno foi o que apresentou melhores resultados de adsorÃÃo. O estudo da cinÃtica de adsorÃÃo apresentou um melhor ajuste ao modelo de pseudo-segunda ordem e a difusÃo intrapartÃcula està envolvida no mecanismo de adsorÃÃo. No estudo das isotermas de equilÃbrio, o resultado mostra melhor ajuste das equaÃÃes de Langmuir e Freundlich pelos dados, com capacidade mÃxima de adsorÃÃo do corante azul de metileno de 819,7 mg/g a 25 ÂC, para a raiz do aguapÃ. A elevaÃÃo na temperatura do sistema provocou aumento na capacidade mÃxima adsorvida e tambÃm provocou um aumento no tempo para o sistema atingir o equilÃbrio. Os valores da constante de velocidade de pseudo-segunda ordem aumentaram com o aumento da temperatura. Um aumento na concentraÃÃo inicial do corante provocou um aumento na quantidade de corante adsorvida. A energia de ativaÃÃo para todos os biosorventes, da ordem de 20 â 40 kJ.mol-1, demonstrou que o processo à de natureza fÃsica. Os parÃmetros termodinÃmicos ∆HÂ, ∆S e ∆GÂ, para a maioria dos biosorventes indicam que o processo à de natureza exotÃrmica, espontÃnea e favorÃvel, com exceÃÃo da esfera de ALG/GC/Biomassa que mostrou valores de natureza endotÃrmica. O estudo de dessorÃÃo demonstrou que os biosorventes podem ser reutilizados.

A síntese de zeólitas a partir de cinzas leves e pesadas de carvão mineral foi realizada por tratamento hidrotérmico alcalino, as quais foram nomeadas ZCL e ZCP, respectivamente. As zeólitas organomodificadas ZML e ZMP foram obtidas a partir da modificação superficial de ZCL e ZCP, respectivamente, utilizando o surfactante catiônico brometo de hexadeciltrimetilamônio. A partir das soluções remanescentes geradas na síntese de ZCL e ZCP foi possível sintetizar duas novas zeólitas. As características físicoquímicas dos nanomateriais zeolíticos sintetizados, bem como de suas respectivas matérias primas, tais como: capacidade de troca catiônica, massa específica, área específica, composição química, mineralógica e morfológica, entre outras, foram determinadas. Os adsorventes ZML e ZMP foram utilizados na remoção dos corantes Azul Direto 71 (DB71) e Rodamina B (RB) de soluções aquosas em sistema de batelada. Desta forma, quatro sistemas DB71/ZML, RB/ZML, DB71/ZMP e RB/ZMP foram investigados. Os modelos de pseudoprimeira ordem e pseudo-segunda ordem foram aplicados aos dados experimentais para o estudo da cinética de adsorção. O modelo de pseudosegunda ordem foi o que melhor descreveu o processo de adsorção de todos os sistemas corante/zeólita organomodificada. O equilíbrio da adsorção foi analisado a partir de quatro modelos de isoterma, sendo eles: Langmuir, Freundlich, Temkin e Dubinin-Radushkevich (D-R). Os resultados mostram que os modelos de Freundlich e Langmuir melhor descreveram os dados experimentais dos sistemas DB71/ZML e DB71/ZMP, respectivamente. Para os sistemas com RB, o modelo de D-R foi o que melhor se ajustou para ambos adsorventes ZML e ZMP. O planejamento fatorial 24 foi aplicado para a análise dos seguintes fatores que influenciam o processo de adsorção: concentração inicial do corante (Co), pH, dose de adsorvente (M) e temperatura (T). De acordo com as condições estudadas concluiu-se, com o intervalo de confiança igual a 95%, que para o sistema DB71/ZML, os fatores e suas interações que mais influenciam foram C0, M, pH, pH*M, pH*C0, M*C0, pH*M*C0, nessa ordem. No sistema DB71/ZMP, a ordem de influência foi: M, C0, pH, pH*M, pH*C0, M*C0, pH*M*C0. Para os sistemas RB/ZML e RB/ZMP, os resultados foram: M, C0, M*C0, pH, pH*M e M, C0, M*C0, respectivamente. O equilíbrio de adsorção foi atingido em cerca de 40 min para todas as amostras. As porcentagens de remoção do DB71 estavam na faixa de 50 80% e 20 50% para ZML e ZMP, respectivamente. A faixa de porcentagens de remoção do RB variou entre 60 80% e 30 50% para ZML e ZMP, respectivamente. / The synthesis of zeolites from mineral coal fly and bottom ash was performed by alkaline hydrothermal treatment, which were named ZFA and ZBA, respectively. Organo-modified zeolites, SMZF and SMZB, were obtained from surface modification of ZFA and ZBA, respectively, using the cationic surfactant hexadecyltrimethylammonium bromide. From the remaining solutions generated in ZFA and ZBA synthesis it was possible to synthesis two new zeolites. The physicochemical characteristics of the synthesized nanomaterials zeolite as well as their respective raw materials, such as cation exchange capacity, density, specific area, chemical composition, mineralogical and morphological, among others, were determined. The adsorbents SMZF and SMZB were used to remove the dyes, Direct Blue 71 (DB71) and Rhodamine B (RB) from aqueous solutions in batch system. Thus, four systems DB71/SMZF, RB/SMZF, DB71/SMZB, RB/SMZB were investigated. The models of pseudo-first order and pseudo-second order were applied to the experimental data for the study the adsorption kinetics. The model of pseudo-second order was the one that best described the adsorption of all dye/organomodified-zeolites systems. The equilibrium adsorption was analyzed from four models isotherm, namely: Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-B). The results show that the model Freundlich and Langmuir best described the experimental data systems DB71/SMZF and DB71/SMZB, respectively. For systems with RB, the model D-R was the best fit for both adsorbents (SMZF and SMZB). The factorial design 24 was applied to the analysis of the following factors influencing the adsorption process: initial concentration of dye (Co), pH, amount of adsorbent (M) and temperature (T). Under the conditions studied it concludes with the confidence interval of 95%, which for the DB71/SMZF system, the factors and their interactions that influence more were C0, M, pH, pH*M, pH*C0, M*C0, pH*M*C0, in that order. In DB71/SMZB system, the order of influence was: M, C0, pH, pH*M, pH*C0, M*C0, pH*M*C0. For RB/SMZF and RB/SMZB systems, the results were: M, C0, M*C0, pH, pH*M and M, C0, M*C0, respectively. The adsorption equilibrium was attained in about 40 min for all samples. The DB71 removal percentages were in the range of 50 80% and 20 50% for ZML and ZMP, respectively. The range of RB removal percentages varied between 60 80% and 30 50% for ZML and ZMP, respectively.

Interações do estado fundamental e espécies transientes, formadas após fotólise e fotossensibilização de 2-ethylaminodiphenylborinate (2APB) e diphenylboronic anhydride (TPhB), foram estudadas por várias técnicas. Os espectros UV mostram uma grande banda de absorção na região do Ultra-violeta. Os espectros de fluorescência mostram o aumento da intensidade de emissão, em 300 nm, que se desloca para o vermelho até 10-3 M. Em concentrações mais elevadas, a intensidade de emissão diminui, provavelmente devido à formação de agregados. Excitação dos organoboranos no UV, em soluções livre de oxigênio, mostram a formação de dois transientes em 300 e 360 nm. Este último, atribuído a espécie triplete, tem uma vida útil de 5 ms em etanol e é totalmente suprimida na presença de oxigênio. A banda em 300 nm não é afetada por oxigênio, tem uma vida útil da ordem de milisegundos e corresponde a uma espécie com radical centrado no boro. O radical também pode ser obtido por transferência eletrônica do estado triplete da Safranina ao organoborano, formando a forma semioxidada do corante. Experimentos EPR, usando DMPO, mostram que a fotólise direta no UV de 2ABP forma o radical arilborano, seguido pela clivagem de uma ligação B-C e formação de radicais fenil. Radicais de boro são formados quando organoboranos são fotossensíveis por Safranina. Na tentativa de se estender o uso de organoboranos em sistemas de poliméricos, sais ônium foi usado para produzir mais iniciadores e melhorar a velocidade de polimerização. Na excitação visível, induzida a produzir iniciadores, o sentitizador (corante *) é oxidado pelo organoborano para formar o cátion radical correspondente (coranteo+) e R3Bo -. Este ânion radical pode iniciar a polimerização ou interagir com sal de ônio, resultando na liberação de uma grande quantidade de radicais que inicia a polimerização mais eficiente. / Ground state interactions and excited states and transients formed after photolysis and photosensitization of 2-ethylaminodiphenylborinate (2APB) and diphenylboronic anhydride (TPhB) were studied by various techniques. The UV spectra show a large absorption band at UV-spectra. The fluorescence spectra show increasing emission intensity with maximum at 300 nm, which shifts to the red up to 10-3 M concentrations. At higher concentrations, the emission intensity decreases, probably due to the formation of aggregates. UV excitation in deareated solutions shows the formation of two transients at 300 and 360 nm. The latter has a lifetime of 5 ms in ethanol and is totally quenched in the presence of oxygen and assigned to the triplet state of organoborane. The 300 nm peak is not affected by oxygen, has a lifetime in the order of milliseconds, and corresponds to a boron-centered radical species originated from the triplet state. The radical can also be obtained by electron transfer from triplet Safranine to the borane forming the semioxidized form of the dye. EPR experiments using DMPO show that the UV-direct photolysis of 2ABP renders initially arylboroncentered radicals followed by the cleavage of a B-C bond and formation of phenyl radicals. Similar boron radicals are formed when 2APB is photosensitized by Safranine. To extend the use of organoboranes in polymeric system, ônium salts was used to produce more initiators and improve the polymerization velocity. In the visible-induced excitation to produce initiators, the sentitizer (dye*) is oxidized by trivalent and neutral organoborane compound to form the corresponding radical cation (dyeo+) and R3Bo-. This radical anion may itself initiate the polymerization or may interact with onium salt, resulting in the release of a lot of radical that can initiate the polymerization more efficiently.