Halogenated organic compounds have had widespread and massive applications in industry, agriculture, and private households, for example, as degreasing solvents, flame retardants and in polymer production. They are released to the environment through both anthropogenic and natural sources. The most common chlorinated solvents present as contaminants include tetrachloroethene (PCE, perchloroethene) and trichloroethene (TCE). These chlorinated solvents are problematic because of their health hazards and persistence in the environment, threatening human and environmental health. Microbial reductive dechlorination is emerging as a promising approach for the remediation of chlorinated solvents in aquifers. In microbial reductive dechlorination, specialized bacteria obtain energy for growth from metabolic dechlorination reactions that convert PCE to TCE, cis-1,2-dichloroethene (cDCE), vinyl chloride (VC), and finally to benign ethene. Field studies show incomplete dechlorination of PCE to ethene due to lack of electron donors or other populations competing for the electron donor. Mathematical models are good tools to integrate the processes affecting the fate and transport of chlorinated solvents in the subsurface. This thesis explores the use of modeling to provide a better understanding of the reductive dehalogenation process of chlorinated solvents and their competition with other microorganisms for available electron donors in continuous flow systems such as a continuous stirred tank reactor (CSTR) and a continuous flow column. The model is a coupled thermodynamic and kinetic model that includes inhibition kinetics for the dechlorination reactions, thermodynamic constraints on organic acids fermentation and has incorporated hydrogen competition among microorganisms such as homoacetogenesis, sulfate reducers and ferric iron reducers. The set of equations are coupled to those required for modeling a CSTR. The system of model equations was solved numerically using COMSOL 3.5 a, which employs finite-element methods. The kinetic model was verified by simulation results compared to previously published models and by electron balances. The simulation process progressed by simulating the anaerobic reductive dechlorination, coupled with thermodynamic limitation of electron donor fermentation in batch systems to the modeling of CSTR, and finally to simulate anaerobic reductive dechlorination in continuous flow column, aquifer column including the processes of advection, dispersion and sorption along with the microbial processes of dehalogenation, fermentation, iron and sulfate reduction. The simulations using the developed model captured the general trends of the chemical species, and a good job predicting the dynamics of microbial population responses either the CSTRs or continuous flow column. Although, the kinetic of anaerobic dechlorination processes of chlorinated solvents in those systems have been researched in the past, little progress has been made towards understanding the combined effects of the dechlorination and thermodynamic constraints in continuous flow systems. This work provides a rigorous mathematical model for describing the coupled effects of these processes. / Graduation date: 2012

A presente pesquisa teve, por principal objetivo, avaliar a viabilidade da desnitrificação autotrófica, empregando sulfeto como doador de elétrons, aplicada a efluentes de reatores anaeróbios tratando esgoto sanitário. Estudos anteriores indicam que o sulfeto presente na fase líquida de efluentes e no biogás pode ser utilizado como doador de elétrons para a desnitrificação. Porém, há poucas informações sobre as interações entre os ciclos do carbono, nitrogênio e enxofre neste processo que permitam a utilização prática dos fundamentos já conhecidos sobre a desnitrificação na presença de sulfeto. Neste trabalho, realizaram-se ensaios de desnitrificação na presença de sulfeto, a fim de se avaliar o potencial de uso desse composto como doador de elétrons. Inicialmente, foram utilizados frascos de 1 L contendo biomassa imobilizada em espuma de poliuretano, alimentados com meio sintético nitrificado contendo sulfeto como doador e nitrito e nitrato como receptores de elétrons. Variou-se a concentração de sulfeto, obtendo-se diferentes relações N/S. Constatou-se desnitrificação completa de ambos os receptores estudados; entretanto, isto só ocorreu com estabilidade para relações N/S inferiores à relação estequiométrica baseada nas reações químicas correspondentes, isto é, quando foi aplicado sulfeto em excesso. Os resultados mostraram que a oxidação total ou parcial dos compostos de enxofre no processo depende da relação N/S, e a velocidade de consumo de nitrato foi maior que a de nitrito. Posteriormente, realizaram-se novos ensaios semelhantes ao anterior, porém, a alimentação consistiu na mistura do efluente sintético nitrificado a efluente de reator anaeróbio tratando água residuária de abatedouro de aves, e o único receptor de elétrons aplicado foi nitrato. Neste caso, foi constatada desnitrificação completa na relação N/S correspondente à estequiometria relativa a sulfeto e nitrato. A cinética de remoção de nitrogênio seguiu modelo de decaimento exponencial de primeira ordem; entretanto, houve limitação à transferência de massa intraparticular e na fase líquida, fato que caracterizou os modelos ajustados como sendo de primeira ordem. As velocidades específicas aparentes obtidas na primeira fase foram próximas de 15 mgN/gSSV.h, tanto com a aplicação de nitrato, quanto de nitrito como receptores de elétrons. Na segunda fase, a máxima velocidade específica aparente de remoção de nitrato foi da ordem de 6 mgN/gSSV.h. / The feasibility of autotrophic denitrification of effluent from anaerobic reactor treating domestic sewage using sulfide as electron donor was evaluated. Prior researches reveals sulfide into liquid phase of effluents and biogas can be utilized as electron donor for denitrification. However, information about the interaction between carbon, nitrogen and sulfur cycles in this process are few to permit practice utilization of known fundamentals about denitrification in presence of sulfide. In this work, laboratory tests of denitrification in the presence of sulfide were carried out to evaluate potential employ of this compound as electron donor. Initially, 1 L flasks with immobilized biomass in polyurethane foam was fed with synthetic nitrified wastewater containing sulfide as donor and nitrite e nitrate as electron acceptors. Sulfide concentration was diversified to obtain different N/S ratios. Complete denitrification occurred with nitrate and nitrite; nevertheless, it was observed in a stable way only for N/S ratios smaller than stoichiometric rate based in the corresponding chemistry reactions, that is, when applied excess of sulfide. The results showed that total or partial sulfur compounds oxidation depends on N/S ratio and the nitrate removal rate was bigger than nitrite removal rate. Afterward, new assays were carried out in the same way. However, the flasks were fed with synthetic nitrified wastewater mixed to effluent from anaerobic reactor treating bird slaughterhouse wastewater, and nitrate was the only electron acceptor applied. In this case, complete denitrification was evidenced for stoichiometric N/S ratio relating to sulfide and nitrate. Nitrogen removal kinetic followed exponential decay model of first order; however, this behavior was due to mass transfer limitation in the liquid phase and intraparticular. Apparent specific rates of nitrogen removal found in the first phase were nearby 15 mgN/gSSV.h, with nitrate as well as nitrite application. In the second phase, maxima apparent specific rate of nitrogen removal in nitrate form was about 6 mgN/gSSV.h.

A remoção de nitrogênio é um aspecto importante do tratamento de águas residuárias, visto que este nutriente causa diversos inconvenientes, com consequentes danos à saúde humana e ao meio ambiente. A forma mais utilizada para a remoção biológica de nitrogênio de águas residuárias é a nitrificação autotrófica seguida de desnitrificação heterotrófica. Esta última etapa necessita de doadores de elétrons orgânicos, provenientes de fontes endógenas ou exógenas. Isto pode encarecer os sistemas de tratamento que utilizam reatores anaeróbios como primeira unidade de tratamento biológico, já que os efluentes destes não possuem matéria orgânica prontamente degradável, exigindo a adição de fontes exógenas de doadores de elétrons. Neste sentido, a desnitrificação autotrófica usando compostos reduzidos de enxofre como doadores de elétrons mostra-se interessante, já que sulfetos são comumente encontrados em efluentes anaeróbios. O objetivo deste projeto de pesquisa é a avaliação da desnitrificação autotrófica usando sulfeto como doador de elétrons para remoção de nitrogênio de efluentes de reatores anaeróbios tratando esgoto sanitário. Para atingir esse objetivo, foram realizados estudos exploratórios, de viabilidade e aplicabilidade do processo. Na primeira etapa, foram operados reatores em batelada para caracterização cinética, operacional e microbiológica do processo. Na segunda etapa, utilizou-se sistema de reatores contínuos em escala de bancada para remoção de nitrogênio de esgoto sanitário sintético. Por fim, na terceira etapa foi operado sistema piloto com nova configuração para tratamento secundário e terciário de esgoto sanitário real. A ocorrência da desnitrificação autotrófica foi detectada nas duas primeiras etapas, e houve indícios de sua presença na terceira etapa da pesquisa. Na primeira etapa, nitrato e nitrito foram aplicados com sucesso como receptores de elétrons, e o processo manteve-se estável apenas quando a relação \'NO IND.X\'POT.-\'/\'S POT.2-\' apresentou valores menores do que a estequiométrica. Modelos cinéticos de ordem zero foram os que melhor se ajustaram aos dados de consumo dos receptores de elétrons, e os parâmetro máximos obtidos foram 7,05 e 5,02 mg N/h.gSSV, para nitrato e nitrito respectivamente. Análises filogenéticas revelaram a presença de organismos semelhantes a Thiobacillus denitrificans, bactéria desnitrificante quimiolitotrófica usualmente associada ao processo. Na segunda e terceira etapas, foi possível a remoção global de nitrogênio de, em média, 40% apenas com doadores de elétrons endógenos, através da nitrificação de 40 a 60% da vazão total e posterior mistura com a fração não-nitrificada. A perda de sulfeto nos reservatórios intermediários do sistema de reatores da segunda etapa foi considerada um obstáculo ao processo, que foi solucionado com a nova configuração proposta na terceira etapa e aplicada em escala piloto. Embora a gama variada de processos possíveis em seu interior não tenha sido completamente elucidada, o sistema piloto promoveu tratamento secundário e terciário de esgoto sanitário, com remoção de nitrogênio e atendimento aos padrões de emissão deste parâmetro. Os resultados obtidos na pesquisa mostraram que o processo é versátil e pode coexistir com outros processos, apresentando viabilidade e potencial no tratamento de efluentes de reatores anaeróbios utilizados no tratamento de esgotos sanitários. / Nitrogen removal is an important aspect of wastewater treatment, for this nutrient causes several issues, with damages to human health and to the environment. The most used technique for biological nitrogen removal from wastewaters is autotrophic nitrification followed by heterotrophic denitrification. The latter needs organic electron donors from endogenous or exogenous sources, which can increase treatment costs for plants that rely on anaerobic reactors as their first biological unit, since their effluents do not have enough readily biodegradable organic matter, demanding the addition of exogenous sources of electron donors. In this way, autotrophic denitrification using reduced sulfur compounds as electron donors could be an interesting alternative, for sulfides are usually present in anaerobically pre-treated effluents. The aim of this research is to evaluate autotrophic denitrification using sulfide as electron donor for nitrogen removal from anaerobically pre-treated domestic sewage. For this, exploratory, viability and applicability studies of the process were performed. In the first part of the experiments, batch assays were conducted for kinetic, operational and microbiological characterization of the process. In the second part, a bench-scale system composed of three continuous reactors was used to remove nitrogen from synthetic domestic sewage. And, finally, in the third part a pilot-scale system presenting a new configuration was operated for secondary and tertiary treatment of real domestic sewage. Autotrophic denitrification was detected in the first two parts, and there were evidences of its presence in the third part of the research. In the first part, nitrate and nitrite were applied successfully as electron acceptors, and the process remained stable only when the \'NO IND.X\'POT.-\'/\'S POT.2-\' ratio was lower than the predicted by stoichiometry. Zero-order kinetic models were the ones that best adjusted to the electron acceptors consumption data, and the maximum obtained parameters were 7.05 and 5.02 mg N/h.gVSS, for nitrate and nitrite respectively. Phylogenetic analyses indicated the presence of organisms similar to Thiobacillus denitrificans, a chemolithotrophic denitrifying bacterium usually associated to the process. In the second and third parts, an average global nitrogen removal of 40% could be achieved using endogenous electron donors only, by nitrifying 40 to 60% of the total flow and later mixing it with the remaining non-nitrified fraction. Sulfide loss in the intermediary tanks of the reactors system operated in the second part was considered an obstacle to the process, which was solved with the new pilot-scale configuration proposed in the third part of the research. Although the wide range of possible processes in its interior was not fully understood, the pilot-scale system promoted secondary and tertiary treatment of domestic sewage, removing nitrogen and obeying the emission standards for this parameter. The results obtained in this research indicated that the process is versatile and can coexist with other processes, being thus viable and presenting potential in the treatment of anaerobically pre-treated domestic sewage.

A remoção de nitrogênio acoplada à oxidação de sulfeto pode ser uma opção adequada para o pós-tratamento de efluentes de reatores anaeróbios, os quais contêm nitrogênio amoniacal, que deve ser nitrificado, e sulfeto, que poderia ser utilizado como doador de elétrons endógeno para a desnitrificação autotrófica. Com base nessa constatação, esta pesquisa propôs a aplicação da nitrificação e desnitrificação autotrófica acoplada à oxidação de sulfeto, em um único reator, para a remoção de nitrogênio de efluentes de reatores anaeróbios tratando esgoto sanitário. Visto que existem lacunas na literatura referente ao processo desnitrificante autotrófico citado, as bases teóricas para a determinação das condições operacionais partiram da caracterização cinética e de aspectos fundamentais da desnitrificação autotrófica com uso de sulfeto como doador de elétrons. Numa primeira etapa, avaliou-se o efeito da concentração de sulfeto na desnitrificação, com uso de nitrato e nitrito como receptores de elétrons, em reatores verticais de leito fixo. Os resultados revelaram que compostos intermediários de enxofre foram principalmente formados quando se aplicou excesso de sulfeto, fato que foi mais evidente com o uso de nitrato. Evidências visuais sugeriram que enxofre elementar foi o principal intermediário formado, o qual também estava sendo utilizado quando aplicadas concentrações estequiométricas de sulfeto relativas a nitrato/nitrito. De modo geral, a desnitrificação autotrófica não foi afetada pela desnitrificação heterotrófica residual via atividade endogênica. Numa segunda etapa, determinou-se a cinética intrínseca da desnitrificação autotrófica via nitrato e nitrito com uso de diferentes concentrações de sulfeto em reatores diferenciais de leito fixo. Este bioprocesso pôde ser descrito por modelo cinético de ordem ½ para biofilmes. As constantes cinéticas variaram entre 0,425-0,658 mg N1/2 / L1/2 h para desnitrificação via nitrito e entre 0,190-0,609 mg N1/2 / L1/2 h para desnitrificação via nitrato. Neste último, o menor valor foi devido ao uso de elétrons doados a partir de compostos intermediários de enxofre formados. Numa terceira etapa, utilizou-se um reator de leito fixo operado em batelada alimentada seqüencial, com ciclos de 8 horas, submetido à aeração intermitente e empregando a desnitrificação autotrófica com uso de sulfeto presente no efluente sanitário, pré-tratado anaerobiamente, como doador de elétrons. O prévio estabelecimento da nitrificação com posterior aplicação de baixas concentrações de sulfeto foi a melhor estratégia de partida do reator. A alimentação em batelada alimentada com aplicação de sulfeto em excesso apenas nos períodos anóxicos foi a melhor estratégia de alimentação, proporcionando eficiência média de 85,7% e 53,0% para nitrificação e desnitrificação, respectivamente. O acúmulo de nitrito foi observado após aplicação de carga de choque de sulfeto, que inibiu as bactérias oxidadoras de nitrito. No entanto, houve dificuldade em se estabelecer a desnitrificação via nitrito em função da toxicidade deste composto aos organismos desnitrificantes instalados no reator. A baixa eficiência global de remoção de nitrogênio e algumas restrições operacionais indicaram que a desnitrificação autotrófica usando sulfeto em um único reator operado em bateladas seqüenciais não foi adequada para a proposta desta pesquisa. / Nitrogen removal coupled with sulfide oxidation may be suitable for the post treatment of effluents from anaerobic reactors. These effluents contain ammonium, which must be nitrified, and sulfide, which could be used as an endogenous electron donor for autotrophic denitrification. Since there are gaps in literature regarding the mentioned autotrophic denitrifying process, the theoretical basis for determination of operating conditions came from the characterization of kinetics and fundamentals aspects of autotrophic denitrification using sulfide as electron donor. In a first step, the effect of sulfide concentration on this bioprocess using nitrate and nitrite as electron acceptors in vertical fixed-bed reactors was evaluated. The results showed that intermediary sulfur compounds were mainly produced when excess of electron donor was applied, which was more evident when nitrate was used. Visual evidences suggested that elemental sulfur was the intermediary compound produced. There was also evidence that the elemental sulfur previously formed was being used when sulfide was applied in stoichiometric concentration relative to nitrate/nitrite. For all conditions assayed, autotrophic denitrification was not affected by residual heterotrophic denitrification via endogenic activity, occurring as a minor additional nitrogen removal process. In a second step, the intrinsic kinetics of sulfide-oxidizing autotrophic denitrification via nitrate and nitrite in systems containing attached cells was determined. Differential reactors were fed with nitrified synthetic domestic sewage and different sulfide concentrations. This bioprocess could be described by a half-order kinetic model for biofilms. The half-order kinetic coefficients ranged from 0.425 to 0.658 mg N1/2 / L1/2 h for denitrification via nitrite and from 0.190 to 0.609 mg N1/2 / L1/2 h for denitrification via nitrate. In this latter, the lower value was due to the use of electrons donated from intermediary sulfur compounds formed. In a third step, a sequencing fed-batch biofilm reactor of 8-h cycles was operated under intermittent aeration, applying autotrophic denitrification using sulfide present in the sanitary effluent, anaerobically pre-treated, as electron donor. The effect of the start-up period and the feeding strategy were evaluated. The previous establishment of nitrification process with subsequent application of sulfide in low concentrations was the best start-up strategy. The fed-batch mode with sulfide application in excess only in the anoxic periods was the best feeding strategy, providing average efficiencies of 85.7% and 53.0% for nitrification and denitrification, respectively. Nitrite accumulation was observed after application of shock loading of sulfide, which inhibited nitrite-oxidizing bacteria. However, it was difficult to establish denitrification via nitrite due to the toxicity of this compound to denitrifying organisms developed inside the reactor. The low overall efficiency of nitrogen removal and some operational constraints indicated that autotrophic denitrification using sulfide in a single sequencing fed-batch reactor was not suitable for the purpose of this research.

Cette thèse s’insère dans un projet d’élaboration et de caractérisation des cellules photovoltaïques organiques classiques et inverses, plus précisément il s’agit d’améliorer les performances des cellules via des couches tampons anodiques et cathodiques originales. Nous avons commencé d’améliorer les couches tampons cathodiques avec différents donneurs d’électrons: phtalocyanine de cuivre CuPc, subphtalocyanine SubPc et dérivés de thiophène organiques. Dans le premier cas de donneur d’électrons (CuPc), nous avons mis en évidence l’effet d’une fine couche d’un composé de césium, utilisée comme couche tampon cathodique dans des cellules inverses, sur la collecte des électrons après un traitement thermique. Nous avons montré aussi que la couche tampon cathodique hybride, Alq3 (9nm) / Ca (3nm) améliore les performances des cellules quelque soit le donneur d’électrons et sans nécessité de recuit. Dans le cas de drivés de thiophène, nous avons montré comment la morphologie de surface des couches organiques peut influencer les performances des cellules photovoltaïques organiques. Et dans le cas de SubPc utilisé dans des cellules inverses, nous avons étudié l’effet de la vitesse de dépôt de la couche SubPc sur sa morphologie. Concernant l’amélioration de la couche tampon anodique, nous avons étudié des cellules classiques à base SubPc et du pentathiophene (5T). Après l’optimisation de l’épaisseur des donneurs d’électrons, nous avons montré que la bicouche MoO3 (3 nm) / Cul (1,5 nm) utilisée comme couche tampon anodique, permet d'améliorer les performances des cellules, quelque soit le donneur d’électrons. Dans le cas du SubPc, nous avons obtenu un rendement qui approche de 5%. / This thesis concerns elaboration and characterization of classical and inverse organic photovoltaic cells, specifically improving the anodic and cathodic buffer layers. We started by improving the cathode buffer layers with different electron donors: copper phthalocyanine CuPc, subphtalocyanine SubPc and thiophene derivatives (BSTV and BOTV). In the first case of electron donor (CuPc), we highlighted the effect of the thin layer of cesium compound, used as a cathodic buffer layer in inverse cells, on the collection of electrons after heat treatment.We have also shown that the hybrid cathodic buffer layer, Alq3 (9 nm) / Ca (3nm) improves the cell performance whatever the electron donor without annealing. In the case of thiophene derivatives, we have shown how the morphology of the organic layers surface can influence the performance of organic photovoltaic cells. In the case of SubPc used in inverse cells, we studied the effect of the deposition rate of the layer on the morphology of SubPc surface.Regarding the improvement of the anodic buffer layers, we investigated those based on the SubPc and pentathiophene (5T) in classical cells. After optimization of the electron donors thickness, we have shown that the bilayer MoO3 (3 nm) / CuI (1.5 nm) used as an anodic buffer layer, improves cell performances, whatever the electron donor. In the case of SubPc, we obtained a efficiency approaching 5%.

Perfluorosulfonate ionomers, such as Nafion® have been shown to demonstrate a profound affinity for large cationic complexes, and the study of polymer-bound cations may provide insight regarding Nafion® morphology by contrasting molecular size with existing models. The trimetallic complex, [{(bpy)2Ru(dpp)}2RhBr2] 5+, is readily absorbed by ion exchange into Na+ -form Nafion® membranes under ambient conditions. The dimensions of three different isomers of the trimetallic complex are estimated to be: 23.6 Å × 13.3 Å × 10.8 Å, 18.9 Å × 18.0 Å × 13.7 Å, and 23.1 Å × 12.0 Å × 11.4 Å, yielding an average molecular volume of 1.2×103 Å3 . At equilibrium, the partition coefficient for the ion-exchange of the trimetallic complex into Nafion® from a DMF solution is 5.7 × 103 . Furthermore, the total cationic charge of the exchanged trimetallic complexes counterbalances 86 ± 2% of the anionic SO3 − sites in Nafion®. The characteristic dimensions of morphological models for the ionic domains in Nafion® are comparable to the molecular dimensions of the large mixedmetal complexes. Surprisingly, SAXS analysis indicates that the complexes absorb into the ionic domains of Nafion® without significantly changing the ionomer morphology. Given the profound affinity for absorption of these large cationic molecules, a more open-channel model for the morphology of perfluorosulfonate ionomers is more reasonable, in agreement with recent experimental findings. In contrast to smaller monometallic complexes, the time- v dependent uptake of the large trimetallic cations is biexponential. This behavior is attributed to a fast initial ion-exchange process on the surface of the membrane, accompanied by a slower, transport-limited ion-exchange for sites in the interior of the ionomer matrix. The development of Nafion®/[{(bpy)2Ru(dpp)}2RhBr2] 5+ modified electrodes is also described for both FTO electrodes and materials made from electrospun carbon mats. The [{(bpy)2Ru(dpp)}2RhBr2] 5+ complexes behave as photocatalytic hydrogen production catalysts in the Nafion® membrane. Furthermore, a second bulk photoelectrolysis experiment with the Nafion®/[{(bpy)2Ru(dpp)}2RhBr2] 5+/FTO electrodes shows an enhancement of catalytic activity compared to the first photoelectrolysis experiment. This enhancement is attributed to halide loss following the first reduction process. Lastly, electrospun carbon nanofiber mats behave as electron donor materials for [{(bpy)2Ru(dpp)}2RhBr2] 5+/Nafion® membranes. / Ph. D.

La thèse intitulée «Design, Synthesis and SupramolecularArchitectures of New Heterocyclic Compounds with PotentialApplications in Material Chemistry and Photovoltaic Conversion” eststructurée en cinq chapitres traitant de nouveaux: a)cyclopenta[c]pyrannes hétérocyclique; b)des propriétés fluorescentes; d) potentiels dispositifs de l'électroniquemoléculaire; d) donneurs moléculaires pour les photovoltaïquesorganiques et e) carbon‘quantum’dots électroluminescents.Le premier chapitre présente une étude des dérivéspseudoazulenique ayant une unité cyclopenta[porte sur leur synthèse, l'analyse structurale et leur comportement dansdes réactions de substitution électrophile pour obtenir des composésayant des propriétés fluorescentes.Le deuxième chapitre présentediastéréoisomères et l'étude de propriétés de fluorescencedérivés d’indenopyrone.Le troisième chapitre décrit la synthèse des nouvellesarchitectures basées sur l’unité cyclopenta[être modifiés structurellement par l'influence d'un stimulus chimiqueou électrochimique afin d'élaborer des potentiels dispositifs del'électronique moléculaire.Dans le quatrième chapitre, la synthèsedes propriétés électroniques des nouvelles molécucellules solaires organiques (OSC) ontLe cinquième et dernier chapitre décrit la passivation desdéfauts de surface des nanoparticules de carbone avec desmolécules organiques ou des polymères pour obtenir desnanoparticules de carbone photoluminescentse surnommé ‘quantum dots. / The thesis entitled “Design, Synthesis and SupramolecularArchitectures of New Heterocyclic Compounds with PotentialApplications in Material Chemistry and Photovoltaic Conversion” isstructured into five chapters concerning new: a) heterocycliccyclopenta[c]pyrans; b) indenopyrone derivatives with fluorescentproperties; c) potential devices of molecular electronics; d)donors for organic photovoltaics and e) electroluminescent carbon‘quantum’ dots.The first chapter presents a study of pseudoazulenederivatives having a cyclopenta[c]pyran unit. The survey comprises thesynthesis, structural analysis and reactivity towards electrophilicsubstitution in order to obtain fluorescent compounds.The second chapter deals with the separation odiastereoisomers and the study of fluorescent propertiesindenopyrone derivatives.The third chapter describes the synthesis of newarchitectures based on cyclopenta[c]pyran unit that can be structurallymodified by the influence of a chemical or electrochemical stimulus inorder to work as potential devices in molecular electronics.In the fourth chapter, the synthesis andelectronic properties of new molecular donors for organic solar cellswas described.The fifth and last chapter outlines the passivation of surfacedefects on carbon nanoparticles using small organic molecules orpolymers in order to obtain photoluminescent carbon nanoparticlesdubbed as carbon‘quantum’dots.

No description available.