Des del seu descobriment, a la molècula C60 se li coneixen una varietat de derivats segons el tipus de funcionalització amb propietats fisicoquímiques específiques de gran interès científic. Una sel·lecció de derivats corresponents a addicions simple o múltiple al C60 s'ha considerat en aquest treball d'investigació. L'estudi a nivell de química computacional de diversos tipus d'addició al C60 s'han portat a terme per tal de poder donar resposta a aspectes que experimentalment no s'entenen o són poc clars.Els sistemes estudiats en referència a l'addició simple al C60 han estat en primer lloc els monoiminoful·lerens, C60NR, (de les dues vies proposades per la seva síntesi, anàlisis cinètic i termodinàmic han ajudat a explicar els mecanismes de formació i justificar l'addició a enllaços tipus [5,6]), i en segon lloc els metanoful·lerens i els hidroful·lerens substituits, C60CHR i C60HR, (raons geomètriques, electròniques, energètiques i magnètiques justifiquen el diferent caràcter àcid ente ambdós derivats tenint en compte una sèrie de substituents R amb diferent caràcter electrònic donor/acceptor). Els fluoroful·lerens, C60Fn, i els epoxid ful·lerens, C60On, (anàlisi sistemàtic dels seus patrons d'addició en base a poder justificar la força que els governa han aportat dades complementàries a les poques que existeixen experimentalment al respecte). / Since the discovery of C60 molecule a large number of derivatives molecules have been described with a great scientific interest of their specific physical and chemical properties. A selection of single and multiple addition products has been considered in this investigation. Study at Computational Chemistry level for this selected derivatives have been carried out in order to give answer to several points that experimentally are not understandable or not enough clear.As single addition derivatives, firstly were studied the monoiminofullerenes, C60NR, (two routes of synthesis have been considered, kinetic and thermodynamic analysis have help to explain formation mechanisms and justify the possible addition at [5,6]-type bonds), and secondly the methanofullerenes and the substituted hydrofullerenes, C60CHR and C60HR, (geometric, electronic, energetic and magnetic reasons justify the different acid character between both series of derivatives taking care on the influence of R substituents with different donor/acceptor character). The fluorofullerenes, C60Fn, and the epoxide fullerenes, C60On, have been studied as multiple addition derivatives (systematic analysis of the addition pattern have been performed in the way to find reasons to justify the driving force of the multiple addition process).

<p>In this thesis, regioregularpoly( 3-hexylthiophene) (rr-P3HT) polymer was used as a light absorption and electron donating material, while the C60 fullerene and its derivative [6,6]-phenyl C61-butyric acid methyl ester (PCBM) were used as electron acceptor materials. The effect of solvent to control the degree of mixing of the polymer and fullerene components, as well as the domain size and charge transport properties of the blends were investigated in detail using P3HT:C60 films. The photo-physical, structural and electrical transport properties of the polymer blends were carried out according to their ratios. A distinctive photoluminescence (PL) quenching effect was observed indicating a photo-induced electron transfer. In this thesis, the effect of solvents on the crystallization and interchain interaction of P3HT and C60 fullerene films were studied using XRD, UV-vis, PL, Raman and FTIR spectroscopy. The polymer blends formed with non-aromatic solvents exhibited an improved crystallinity and polymer morphology than that formed with aromatic solvents. An improved ordering was demonstrated in the polymer films spin coated from non-aromatic solvents. This indicates that the limited solubility of rr P3HT in a marginal solvent such as non-aromatic solvents can offer a strategy to obtain highly ordered crystal structures and lead directly to optimal morphologies on the films.</p>

The discovery and subsequent synthesis of metal containing fullerenes- IFS (Inorganic Fullerene-like Structures) by R. Tenne et al. has generated considerable scientific interest with great potential impact in many industrial application areas such as lubrication. The lubrication mechanism (tribofilm formation) via exfoliation and deposition of the atomic layers from this cage-like IF-particles was revealed and demonstrated first by this research group. The incorporation of the nanoparticles into lubricants (oils, greases) is however not straightforward. When two surfaces are sliding against each other and a lubricant is used, a thin layer (tribofilm) is formed on the contact area. The friction reducing effects of the nanoparticles can be altered or hindered by certain additives that are used in lubricative oils. The effects of such additives on the tribological behavior of the nanoparticles are investigated by analyzing the tribofilms formed on the worn surfaces using energy-dispersive X-ray spectroscopy in a scanning electron microscope. Another challenge of nanoparticles in lubricants is the penetration of the nanoparticles into the contact zone. A possible solution of this problem is briefly discussed. A modified burnishing technique can be used to coat sliding metallic surfaces with a friction reducing tribofilm. The morphology and composition of these tribofilms was investigated with analytical electron microscopy techniques. In the second part of the thesis electron microscopy was used to investigate the material transfer. Titanium is an elements with high adhesive ability to the counter surface, it displays poor tribological properties in sliding metallic contacts. This can lead to material transfer and consequently severe surface damage. The cold formation and machining of titanium, thus can lead rapid tool wear and poor surface finish. Electron microscopy techniques were used to study the mechanism of titanium transfer to different counter surfaces.

A long-term goal within the field of organic electronics has been to developflexible and functional devices, which can be processed and patterned withlow-cost and energy-efficient solution-based methods. This thesis presents anumber of functional paths towards the attainment of this goal via thedevelopment and demonstration of novel fabrication and patterningmethods involving the important organic-semiconductor family termedfullerenes.Fullerenes are soccer-shaped small molecules, with two often-employedexamples being the symmetric C60 molecule and its more soluble derivative[6,6]-phenyl-C61-butyric acid methyl ester (PCBM). We show that PCBM canbe photochemically transformed into a dimeric state in a bi-excited reactionprocess, and that the exposed material features a significantly reducedsolubility in common solvents as well as an effectively retained electronmobility. This attractive combination of material properties allows for adirect and resist-free lithographic patterning of electronic PCBM films downto a smallest feature size of 1 µm, using a simple and scalable two-stepprocess constituting light exposure and solution development. In a furtherdevelopment, it was shown that the two-step method was useful also in thearea-selective transformation of fullerene/conjugated-polymer blend films,as demonstrated through the realization of a functional complementary logiccircuit comprising a 5-stage ring oscillator.In another project, we have synthesized highly flexible, single-crystal C60nanorods with a solution-based self-assembly process termed liquid-liquidinterfacial precipitation. The 1-dimensional nanorods can be deposited fromtheir synthesis solution and employed as the active material in field-effecttransistor devices. Here, it was revealed that the as-fabricated nanorods canfeature an impressive electron mobility of 1.0 cm2 V-1 s-1, which is on par withthe performance of a work horse in the transistor field, viz. vacuumdeposited amorphous Si. We further demonstrated that the processability ofthe nanorods can be improved by a tuned light-exposure treatment, duringwhich the nanorod shell is polymerized while the high-mobility interior bulkis left intact. This has the desired consequence that stabile nanoroddispersions can be prepared in a wide range of solvents, and we anticipatethat functional electronic devices based on solution-processable nanorodscan be realized in a near future.

Η θεραπεία του καρκίνου αποτελεί στις μέρες μας μία από τις μεγαλύτερες προκλήσεις της επιστημονικής κοινότητας παγκοσμίως. Τα συμβατικά φάρμακα που κυκλοφορούν εδώ και χρόνια προσβάλλουν τόσο τα καρκινικά όσο και τα υγιή κύτταρα. Το αποτέλεσμα είναι η πρόκληση σοβαρών παρενεργειών, οι οποίες δεν επιτρέπουν τη χορήγηση θεραπευτικών δόσεων. Η ανάπτυξη της νανοτεχνολογίας έχει βοηθήσει κατά πολύ το επιστημονικό πεδίο όσον αφορά τη διάγνωση και τη θεραπεία του καρκίνου. Τα νανοσωματίδια παρέχουν ένα νέο τρόπο χορήγησης των αντικαρκινικών φαρμάκων, λειτουργώντας ως φορείς που εξαγγειώνονται στην περιοχή του όγκου, επιτρέποντας με αυτόν τον τρόπο άμεση πρόσβαση στα καρκινικά κύτταρα. Τα συγκεκριμένα σωματίδια μπορούν να τροποποιηθούν κατάλληλα, ώστε να αποκτήσουν τη δυνατότητα να δεσμευθούν στις μεμβράνες των καρκινικών κυττάρων, στο μικροπεριβάλλον τους ή σε κυτταροπλασματικούς ή πυρηνικούς υποδοχείς. Κατά συνέπεια, μεταφέρονται στοχευμένα υψηλές συγκεντρώσεις του φαρμάκου στα καρκινικά κύτταρα και μειώνεται η τοξικότητα στους φυσιολογικούς ιστούς. Η ανάπτυξη τροποποιημένων νανοφορέων για τη χορήγηση των αντικαρκινικών φαρμάκων μπορεί να περιορίσει τα προβλήματα που συνδέονται με τα συμβατικά συστήματα χορήγησης, όπως έλλειψη εκλεκτικότητας και τοξικότητα. Οι νανοφορείς που έχουν μελετηθεί μέχρι σήμερα, εμφανίζουν σημαντικά προβλήματα, όπως δομική αστάθεια, δομική ετερογένεια και ελλειπή έλεγχο μεγέθους και σχήματος. Υπάρχει, συνεπώς, μια αυξανόμενη ανάγκη για ανάπτυξη προηγμένων συστημάτων μεταφοράς αντικαρκινικών φαρμάκων, στα οποία το σχήμα, το μέγεθος και η ικανότητα φόρτωσης να μπορούν να ρυθμιστούν κατάλληλα, προκειμένου να μεγιστοποιηθεί η αποτελεσματικότητα και να ελαχιστοποιηθεί η τοξικότητα των φαρμάκων. Τα φουλλερένια (C60) ανήκουν στην κατηγορία των νανοφορέων που μελετούνται εκτενώς για τη χορήγηση αντικαρκινικών παραγόντων. Η δυνατότητα των φουλλερενίων για την εκπλήρωση των παραπάνω προδιαγραφών έγκειται στη μεγάλη δυνατότητα τροποποίησης της βασικής τους δομής και την παρασκευή πληθώρας παραγώγων με επιθυμητές ιδιότητες. Το μεγαλύτερο μειονέκτημα αυτών των μορίων είναι η ελάχιστη διαλυτότητά τους στο νερό. Το πρόβλημα αυτό μπορεί να αντιμετωπιστεί με την πρόσδεση σε αυτά υδρόφιλων πολυμερών, όπως είναι η πολυαιθυλενογλυκόλη (PEG). Στην παρούσα εργασία, παρουσιάζονται τα αποτελέσματα της σύνθεσης ενός συζεύγματος πεγκυλιωμένου μορίου φουλλερενίου (C60) με το αντικαρκινικό φάρμακο δοξορουμπικίνη, καθώς και η in vitro αξιολόγηση του τελικού προϊόντος. Στόχος είναι η αύξηση της αποτελεσματικότητας και η μείωση της τοξικότητας του φαρμάκου, μέσω στοχευμένης μεταφοράς στον καρκινικό όγκο. Ένα πεγκυλιωμένο σύζευγμα φουλλερενίου (C60) με δοξορουμπικίνη (FULL-PEG-DOX) συντέθηκε επιτυχώς σε έξι στάδια με συνολική απόδοση 25,7% και χαρακτηρίστηκε με 1H-NMR, IR και UV. Η δραστικότητα του τελικού προϊόντος, καθώς επίσης και δύο ενδιάμεσων προϊόντων (FULL-PEG και FULL-DOX) αλλά και του υδροχλωρικού άλατος της δοξορουμπικίνης ενάντια στον καρκίνο ελέγχθηκε in vitro σε καρκινικές σειρές κυττάρων MCF-7. Το τελικό προϊόν εμφάνισε ικανοποιητική αντικαρκινική δράση, κυρίως μέσω αναστολής του πολλαπλασιασμού των καρκινικών κυττάρων. Τα αποτελέσματα της μελέτης μπορούν να θεωρηθούν ιδιαίτερα ενθαρρυντικά και δικαιολογούν τη συνέχιση της ερευνητικής προσπάθειας για στοχευμένη χορήγηση δοξορουμπικίνης σε καρκινικά κύτταρα μέσω της πρόσδεσής της σε τροποποιημένα μόρια φουλλερενίου. / Cancer’s treatment is nowadays one of the most important challenges that the scientific community worldwide has to face. Conventional anticancer drugs, which are in the market many years, affect both cancer and normal cells. Hence, they cause serious side effects, which make the administration of therapeutic drug doses impossible. The development of nanotechnology has changed the scientific landscape in terms of cancer diagnosis and treatment. Nanoparticulate drug carriers provide a new mode of cancer drug delivery. They can extravasate at tumor site, allowing direct drug access to cancer cells. These particles allow exquisite modification for binding to cancer cell membranes, the microenvironment or to cytoplasmic or nuclear receptor sites. This results to the delivery of high drug concentrations to the targeted cancer cells with reduced toxicity to normal (healthy) tissue. The application of engineered nanocarriers for the delivery of anticancer drugs may alleviate the problems associated with conventional anticancer drug delivery systems, such as lack of selectivity and toxicity. Drug nanocarriers explored to date suffer from inherent limitations, including instability, structural heterogeneity and poor control over size and shape. There is an increasing need for advanced delivery agents for the anticancer drugs where shape, size, functionalization and loading capacity can be precisely tuned in order to maximize efficacy and minimize drug toxicity. Among the nanocarriers which are currently studied as drug delivery systems for anticancer agents are fullerenes (C60). The potential of fullerenes to address the above specifications lies in the immense scope for chemical derivatization to the basic structure. Except for their high toxicity to normal cells, the main drawback of these carbon molecules is their poor solubility to water. This problem can be overcome by attaching on fullerene particles hydrophilic polymers, such as polyethylene glycol (PEG). In the present work, the results of synthesis and in vitro biological evaluation of a pegylated fullerene conjugate with the potent anticancer drug Doxorubicin are represented. The main goal is to increase efficacy and reduce toxicity of doxorubicin, through targeted delivery to tumors, by conjugating the drug to pegylated fullerenes. A pegylated fullerene-doxorubicin conjugate has been successfully synthesized in 6 steps with a 25.7 % overall yield and was characterized by 1H-NMR, IR and UV. The final product, two intermediate products and doxorubicin hydrochloride were evaluated in vitro against MCF-7 cancer cells lines. The final product exhibited satisfactory anticancer activity mainly by inhibiting proliferation. The results of this study justify further investigation of the potential of pegylated fullerenes as targeted nanocarriers of doxorubicin.

Philosophiae Doctor - PhD / In this thesis, regioregularpoly( 3-hexylthiophene) (rr-P3HT) polymer was used as a light absorption and electron donating material, while the C60 fullerene and its derivative [6,6]-phenyl C61-butyric acid methyl ester (PCBM) were used as electron acceptor materials. The effect of solvent to control the degree of mixing of the polymer and fullerene components, as well as the domain size and charge transport properties of the blends were investigated in detail using P3HT:C60 films. The photo-physical, structural and electrical transport properties of the polymer blends were carried out according to their ratios. A distinctive photoluminescence (PL) quenching effect was observed indicating a photo-induced electron transfer. In this thesis, the effect of solvents on the crystallization and interchain interaction of P3HT and C60 fullerene films were studied using XRD, UV-vis, PL, Raman and FTIR spectroscopy. The polymer blends formed with non-aromatic solvents exhibited an improved crystallinity and polymer morphology than that formed with aromatic solvents. An improved ordering was demonstrated in the polymer films spin coated from non-aromatic solvents. This indicates that the limited solubility of rr P3HT in a marginal solvent such as non-aromatic solvents can offer a strategy to obtain highly ordered crystal structures and lead directly to optimal morphologies on the films. / South Africa

Submitted by MARCIA ROVADOSCHI (marciar@unifra.br) on 2018-08-16T20:05:43Z No. of bitstreams: 2 Dissertação_LauraFernandaOsmariVendrame.pdf: 3061643 bytes, checksum: d06cb3bc35f9d2bedf0c39b9c8e35276 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-08-16T20:05:43Z (GMT). No. of bitstreams: 2 Dissertação_LauraFernandaOsmariVendrame.pdf: 3061643 bytes, checksum: d06cb3bc35f9d2bedf0c39b9c8e35276 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-03-31 / The use of C60 fullerenes, functionalized or in pristine form, as chemical and biological sensors has become a large field of study and application High stability and low chemical reactivity of these nanostructures provide some difficulties in studying the chemical and physical properties. These difficulties can be overcome through the functionalization process. The purpose of this work is to evaluate through abs initio calculations the structural and electronic properties of the temozolamide molecule interacting with functionalized fullerenes. This drug is very important for the treatment of brain tumors. This study is based on the density functional theory, using the SIESTA computational code. First of all, it was evaluated the isolated functionalized fullerenes behavior, as well as the temozolamide molecule. Subsequently, it was studied the interaction of functionalized fullerenes with temozolamide in order to understand the energetic and structural properties of these structures to support the use of these nanomaterials in future biomedical applications. From the results it is possible to observe the depending on the studied configuration, the binding energy values are not the same. It was found a weak interaction for all functionalized C60 interacting with temozolamide through physical adsorption, with values between 0.43 eV and 1.02 eV for all stable configurations. An interaction through physical adsorption was also observed for themozolamide with pristine fullerenes, with energy value of 0.23 eV. Despite some high energy values, the distance in the interaction between the nearest atoms of the nanostructure and temozolomide does not represent chemical bonds. The interaction of the temozolamide drug with fullerenes is important for the future development of central nervous system nanodrugs improving the performance and slowing the elimination of the drug by the body. / O uso de fulerenos C60, funcionalizados ou na forma pura, como carreadores de fármacos tem se tornado um grande campo de estudo e aplicação. A alta estabilidade e baixa reatividade química destas nanoestruturas trazem algumas dificuldades de manipulação no estudo de suas propriedades químicas e físicas. Estas dificuldades podem ser superadas através do processo de funcionalização. O objetivo deste trabalho é avaliar, por meio de cálculos ab initio as propriedades estruturais e eletrônicas da molécula de temozolamida interagindo com fulerenos puros e funcionalizados. A temozolamida é um medicamento muito importante no tratamento de tumores cerebrais. Este estudo é baseado na teoria do funcional da densidade, utilizando o código computacional SIESTA. Primeiramente, estudamos os fulerenos funcionalizados isolados, bem como a molécula de temozolamida. Posteriormente, estudamos a interação do fulereno puro e funcionalizado, com a temozolamida a fim de compreender suas propriedades energéticas e estruturais. A partir dos resultados é possível observar que, dependendo da configuração estudada, os valores de energia de ligação não são os mesmos. Obtivemos uma interação fraca para todos os C60 funcionalizados interagindo com a temozolamida via adsorção física, com valores entre 0,43 eV e 1,02 eV para as configurações mais estáveis. Uma interação via adsorção física tambem foi observada para a interação da temozolamida com fulerenos puros, com energia de 0,23 eV Apesar de alguns valores altos de energia, a distância na interação entre os átomos mais próximos entre a nanoestrutura e a temozolamida e a baixa transferência de carga, não representam características de ligações covalentes. A interação da temozolamida com fulerenos, através da funcionalização, neste estudo, é importante para contribuir com o futuro desenvolvimento de nanomedicamentos do sistema nervoso central melhorando o desempenho e reatardando a eliminação do medicamento pelo organismo.

Orientadores: Ana Flávia Nogueira, Valtencir Zucolotto / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T02:59:18Z (GMT). No. of bitstreams: 1 Almeida_LuizCarlosPimentel_D.pdf: 6880507 bytes, checksum: f7a2c24853f25411226ae9b66a2de97b (MD5) Previous issue date: 2012 / Resumo: Neste trabalho foram estudados filmes finos multicamadas baseados em polímeros condutores, nanotubos de carbono e um derivado de fulereno. Esses filmes foram depositados pela técnica de deposição camada por camada (LbL) via interações eletrostáticas. Esse trabalho está dividido em duas partes: 1-) Filmes LbL baseados no polímero conjugado poli(p-fenilenovinileno) (PPV) e nanotubos de carbono de parede única funcionalizados com grupos carboxílicos (SWNTCOOH) foram preparados em arquitetura de bloco, caracterizados e aplicados como fotoeletrodos em células solares fotoeletroquímicas. A morfologia desses filmes foi avaliada por microscopia de força atômica (AFM) e de epifluorescência, as quais indicaram uma variação morfológica significativa dos filmes após adição de camadas de nanotubos de carbono. A transferência de carga fotoinduzida do polímero condutor PPV para o SWNT-COOH foi analisada por supressão de fotoluminescência (PL). A caracterização fotoeletroquímica foi realizada sob irradiação de luz branca e os fotoeletrodos contendo SWNT-COOH apresentaram valores de fotocorrente de até 7,5 mA cm. A fotocorrente aumentou e tornou-se mais estável quando uma camada do polímero poli(3,4-etilenodioxitiofeno) dopado com poli(4-sulfonato de estireno) (PEDOT:PSS) foi depositada entre o eletrodo ITO e o filme LbL. 2-) Foram preparados filmes LbL baseados no polímero conjugado poli[2-(3-tienil)-etoxi-4-butilsulfonato] de sódio (PTEBS) e no derivado de fulereno C60-F. A caracterizacao fotofísica mostrou a ocorrência de transferência fotoinduzida de carga do PTEBS para o C60-F, a qual foi também demonstrada por meio da geração de fotocorrente obtida quando os filmes (PTEBS/C60-F) foram aplicados como fotoeletrodos em células solares fotoeletroquímicas. Os resultados obtidos fazem dos filmes LbL baseados em semicondutores orgânicos candidatos promissores para conversão de energia solar. / Abstract: In this work, multilayer thin films based on conducting polymers, carbon nanotubes and fullerene derivatives were studied. These films were fabricated by layer-by-layer deposition technique (LbL) through electrostatic interactions. This work is divided in two parts: 1-) LbL films composed of a conducting polymer poly(p-phenylenevinylene) (PPV) and carboxylic acid functionalized singlewalled carbon nanotubes (SWNT-COOH) were prepared in a block architecture, characterized and applied as electrodes in photoelectrochemical solar cells. Film morphology was evaluated by atomic force and epifluorescence microscopies, showing remarkable changes after incorporation of SWNT-COOH layers. The photoinduced charge transfer from the conducting polymer to SWNT-COOH was analyzed by photoluminescence (PL) quenching. Photoelectrochemical characterization was performed under white light and the films containing SWNTCOOH displayed photocurrent values up to 7.5 mA cm. Photocurrent generation was enhanced and became more stable when an intermediate layer of poly(3,4- ethylenedioxythiophene)¿poly(4-styrenesulfonic acid) (PEDOT:PSS) was interposed between the ITO electrode and LbL films. 2-) LbL films based on the conducting polymer sodium poly[2-(3-thienyl)-ethoxy-4-butylsulfonate] (PTEBS) and fullerene derivative C60-F were fabricated. Photophysical characterization shows the occurrence of photoinduced charge transfer from PTEBS to C60-F, which was also demonstrated by photocurrent generation obtained when (PTEBS/C60-F) multilayer films were applied as electrodes of photoelectrochemical solar cells. All these results make the LbL films based on organic semiconductors promising canditates towards solar energy conversion. / Doutorado / Físico-Química / Doutor em Ciências

Dans le domaine des nanomachines, des progrès considérables ont été réalisés. Il est désormais possible de synthétiser une machine moléculaire et de contrôler son mouvement grâce à une source d'énergie chimique, lumineuse ou électrique, de façon à ce qu'il soit unidirectionnel. Un nouveau défi a surgi : comment rendre ce mouvement utile ? Comment utiliser le travail d'une machine moléculaire au niveau nanoscopique, mésoscopique ou macroscopique ? Cette thèse s'inscrit à la suite de la démonstration du contrôle de la rotation d'un moteur moléculaire. Ce moteur est un complexe de ruthénium(II) dont la rotation de la partie mobile, le rotor, est contrôlée par la pointe d'un microscope à effet tunnel. Afin de déterminer le travail limite fournit par ce moteur, nous avons synthétisé un nanotreuil intégrant le moteur moléculaire déjà étudié dans l'équipe avec une chaîne latérale permettant d'accrocher par chimie clic différents types de fragments moléculaires. Ces fragments ayant des natures chimiques différentes (fullerènes, triptycènes, porphyrines), ils interagiront de manière plus ou moins importante avec la surface. De ce fait, la rotation du moteur pourra ou ne pourra pas entraîner leur déplacement sur la surface, ce qui nous permettra d'estimer le travail du moteur. Cette thèse décrit la synthèse des différentes sous-unités de ce nanotreuil : le moteur dissymétrique, la chaîne et les différentes charges. Après avoir développé différentes stratégies visant à intégrer la chaîne sur le rotor, la synthèse de chacun des fragments moléculaires fera l'objet des chapitres suivants. Enfin, un chapitre mettra en perspective l'intégration possible du moteur dans des systèmes d'engrenages en vue de la récupération du travail dans un réseau supramoléculaire. / In the field of molecular machines, considerable developments have been achieved. Nowadays, it is possible to synthesize a molecular machine with a directional control on its motion thanks to chemical, light or electrical energy source. A new challenge has arised: how make that movement useful ? How use the work of a molecular machine at a nano-, meso- or macro-level ? This thesis is in line with the demonstration and control of the molecular motor rotation. This motor consists in a ruthenium(II) complexe whom rotation of the movable part, i.e. the rotor, is controlled by the scanning tunnelling microscope tip. In order to estimate its motive power, we have synthesized a nanowinch incorporating the molecular motor synthesized in the team. This motor has been desymmetrized to be able to incorporate a chain allowing to connect by click chemistry several kind of molecular fragments. These fragments (fullerenes, triptycenes, porphyrines) will interact more or less with the surface of deposition. Therefore, the motor rotation will or will not make them move on the surface, giving us the possibility to estimate the motor torque. In this thesis, the synthesis of the different parts of the nanowinch is described : the dissymmetric molecular motor, the linker and the loads. After developping the synthetic strategies allowing us to incorporate the linker on the rotor, the synthesis of each fragment will be detailled in the following chapters. A concluding chapter will deal with the possible integration of that type of complexes into molecular gears in order to exploit the torque in a supramolecular network.

Polymer solar cells form a promising technology for converting sunlight into electricity, and have reached record efficiencies over 10% and lifetimes of several years. The performance of polymer solar cells depends strongly on the distribution of electron donor and acceptor materials in the active layer. To achieve longer lifetimes, degradation processes in the materials have to be understood. In this thesis, a set of complementary spectroscopy and microscopy techniques, among which soft X-ray techniques have been used to determine the morphology of polymer:fullerene based active layers. We have found that the morphology of TQ1:PC70BM films is strongly influenced by the processing solvent and the use of solvent additives. We have also found, by using soft X-ray techniques, that not only the light-absorbing polymer TQ1, but also the fullerene is susceptible to photo-degradation in air. Moreover, the fullerene degradation is accelerated in the presence of the polymer. Additionally, this thesis addresses the role of the interfacial layers for device performance and stability. The commonly used hole transport material PEDOT:PSS has the advantage of being solution processable at room temperature, but this layer is also known to contribute to the device degradation. We have found that low-temperature processed NiOx is a promising alternative to PEDOT:PSS, leading to improved device performance. Even for encapsulated polymer solar cells, some photo-induced degradation of the electrical performance is observed and is found to depend on the nature of the hole transport material. We found a better initial stability for solar cells with MoO3 hole transport layers than with PEDOT:PSS. In the pursuit of understanding the initial decrease in electrical performance of PEDOT:PSS-based devices, simulations were performed, from which a number of degradation sources could be excluded. / With the increasing global demand for energy, solar cells provide a clean method for converting the abundant sunlight to electricity. Polymer solar cells can be made from a large variety of light-harvesting and electrically conducting molecules and are inexpensive to produce. They have additional advantages, like their mechanical flexibility and low weight, which opens opportunities for novel applications. In order for polymer solar cells to be more competitive, however, both the power conversion efficiencies and lifetimes need to further improve. One way to achieve this is to optimize the morphology of the active layer. The active layer of a polymer solar cell consists of electron donating and electron accepting molecules whose distribution in the bulk of the film is a major factor that determines the solar cell performance. This thesis presents the use of complementary spectroscopy and microscopy methods to probe the local composition in the active layer of polymer solar cells. The stability of the active layer is studied and the interplay between the photo-degradation of the donor and acceptor molecules is investigated. Additionally, this thesis addresses how the interfacial layers between the active layer and the electrodes can influence device performance and stability. / <p>I publikationen felaktigt ISBN 978-91-7063-739-1</p>