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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Ordered Structures from Nanoparticles/Block Copolymer Hybrids: Ex-situ Approaches toward Binary and Ternary Nanocomposites

Horechyy, Andriy 28 July 2011 (has links) (PDF)
Within the field of modern technology, nanomatrials, such as nanoparticles (NP), nanorods (NR), quantum dots (QD) etc. are, probably, the most prominent and promising candidates for current and future technological applications. The interest in nanomaterials arise not only form the continuous tendency towards dimensions minimisation of electronic devices, but also due to the fact, that new and, often, unique properties are acquired by the matter at the length scale between 1 and 100 nm. The ability to organize nanoparticles into ordered arrays extends the range of useful NP-based systems that can be fabricated and the diversity of functionalities they can serve. However, in order to successfully exploit nanoparticle assemblies in technological applications and to ensure efficient scale-up, a high level of direction and control is required. Recently, block copolymers (BCP) have attracted much attention as a powerful and very promising tool for creation of nanoscale ordered structures owing to their self-assembling properties. In addition, these systems offer the possibility to fabricate nanostructured composite materials via incorporation of certain nanoadditives (i.e. NPs). The concept is that by selective inclusion of the nanoparticles into one of the blocks of a self-assembling copolymer, the nanoparticles are forced into a defined spatial arrangement determined by the phase morphology of the block copolymer. In present work self-assembling phenomena of block copolymers was exploited to fabricate binary (NP/BCP) and ternary (NP1/NP2/BCP) composites, filled with pre-synthesized nanoparticles of various nature. Polystyrene-block-polyvinylpyridine block copolymers (PS-b-PVP) of various composition and molecular weight were used for fabrication of nanocomposites. The first part of the thesis focuses on fabrication of functional BCP-based composites containing magnetic nanoparticles (MNP), selectively assembled within one of the blocks of BCP matrix. Magnetic nanoparticles (MNPs) were selected among others since, as for today, there is the least number of successful results reported in literature on their selective incorporation into one of the phases of a BCP matrix. From the application point of view fabrication of periodic arrays of “magnetic domains” with periodicity on nanometer scale is also of interest for potential use in high-density magnetic data storage devices. For this purpose, ferrite-type MNP (Fe3O4, CoFe2O4) having apparent affinity toward polyvinylpyridine (PVP) phase were prepared using simple one-pot synthesis. Highly selective nanoparticles segregation into PVP domains of BCP was achieved owing to the presence of sparse stabilizing organic shell on the nanoparticles surface. Importantly, as-prepared MNPs did not require any additional surface modification step to acquire affinity towards PVP phase. Appropriate selection of annealing conditions allowed to produce patterns of nearly perfect degree of lateral order over relatively large surface large area (more than 4 sq µm). The second task of present work was fabrication of ternary NP1/NP2/BCP hybrid composites with two different types of nanoparticles being selectively localized in different microdomains of phase segregated block copolymer matrix. So far as only few studies have been reported on developing of approaches toward ternary composites, creation of alternative and straight forward routes toward such systems is still a challenge. In the frame of this part of present work, silver nanoparticles (AgNPs) covered with polystyrene shell were prepared, with the purpose to be incorporated into polystarene phase of phase separated PS-b-PVP block copolymer matrix. Two different approaches were tested to achieve desired three-component system. First, supposed simple blending of block copolymer and two kinds of nanoparticles having specific affinity toward different blocks of BCP in common solvent. After preparation of MNP/AgNP/BCP composite thin film and subsequent solvent vapour annealing, different domains of microphase segregated PS-b-PVP BCP were filled with different type of nanoparticles. Alternatively, step-wise approach for nanoparticles incorporation was developed and implemented for successful selective nanoparticles incorporation. For this purpose polystyrene stabilized AgNPs (i.e. NP1) were initially mixed with PS-b-PVP BCP to produce composite thin films having nanoparticles selectively located within PS microdomains, while citrate-stabilized second type nanoparticles (i.e NP2) were deposited from their aqueous solutions into PVP domains of AgNP/PS-b-PVP composites. By partition of nanoparticles incorporation procedure into two distinct steps it was also possible to increase effective loading of each type of NPs into BCP matrix.
22

Etudes de surfaces métalliques nanolithographiées : application à la diffusion Raman exaltée de surface / Nanopatterning of metallic surfaces by force-assisted Atomic Force Microscopy lithography : application to SERS

Edely, Mathieu 13 December 2016 (has links)
Depuis la première observation du phénomène de Diffusion Raman Exaltée de Surface (DRES) en 1974 de nombreuses méthodes ont été développées pour contrôler l'arrangement de nanostructures métalliques sur une surface dans le but d'augmenter le signal de diffusion Raman. La valeur du facteur d'amplification de la DRES résulte principalement de l’accroissement localisé du champ électromagnétique pour des surfaces métalliques nanostructurées. Des études antérieures ont révélé que l'espacement nanométrique entre les nanoparticules constituait des zones de forte exaltation appelées «points chauds». Nous avons développé et breveté une méthode de lithographique assistée par AFM permettant la fabrication de surfaces métalliques. Il a été démontré que cette méthode fournissait une approche relativement simple pour réaliser d’une part des surfaces reproductibles à géométrie contrôlée à l’échelle nanométrique, et d’autre part des surfaces modèles pour étudier l'influence de la géométrie des motifs sur l'effet DRES. Afin d'étudier la relation entre les propriétés optiques et la géométrie de nos systèmes la résonance plasmon localisée de surface (LSPR) et le facteur d'exaltation du champ électrique local ont été simulés par éléments finis. Les zones de forte exaltations ont été localisées sur les nanostructures par microscopie par photoémission d'électrons (PEEM) et l'effet DRES a été démontré en effectuant des mesures Raman avec plusieurs molécules cibles. Les corrélations effectuées entre les résultats de PEEM, les calculs du champ local et les facteurs d’exaltation Raman seront présentées en lien avec les paramètres géométriques des motifs de nanostructures. / Since the first observation of Surface Enhanced Raman Scattering (SERS) in 1974 a variety of methods have been developed to physically control the arrangement of metallic nanostructures onto a surface in order to enhance Raman signals. The magnitude of the SERS enhancement factor is mainly driven by the enhanced local electromagnetic field in nanostructured metal surfaces. Gaps between adjacent nanoparticles give rise to strong enhancement effects, often referred as ‘hot spots’. One way to produce highly efficient SERS substrates is to develop a reproducible system of interacting metal nanostructures capable of high field enhancement.We patented a force-assisted Atomic Force Microscopy lithographic method allowing the fabrication of a metallic substrate. It will be shown that this method also provides a relatively simple approach to realize reproducible patterns with controlled geometry that can be used to study the influence of specific pattern geometry on SERS phenomenon.In order to investigate the relationship between optical properties and pattern geometries, localized surface plasmon resonance (LSPR) and local electric field enhancement are simulated.Whereas electric field enhancement regions (hot spot) have been observed on the top of the nanostructures with PhotoEmission Electron Microscopy (PEEM), SERS effect has been demonstrated by performing Raman measurements using several probe molecules. Correlations between PEEM measurements, Raman exaltation and local field calculations are presented in relation with the geometrical parameters of the nanostructured patterns.
23

Ordered Structures from Nanoparticles/Block Copolymer Hybrids: Ex-situ Approaches toward Binary and Ternary Nanocomposites

Horechyy, Andriy 01 July 2011 (has links)
Within the field of modern technology, nanomatrials, such as nanoparticles (NP), nanorods (NR), quantum dots (QD) etc. are, probably, the most prominent and promising candidates for current and future technological applications. The interest in nanomaterials arise not only form the continuous tendency towards dimensions minimisation of electronic devices, but also due to the fact, that new and, often, unique properties are acquired by the matter at the length scale between 1 and 100 nm. The ability to organize nanoparticles into ordered arrays extends the range of useful NP-based systems that can be fabricated and the diversity of functionalities they can serve. However, in order to successfully exploit nanoparticle assemblies in technological applications and to ensure efficient scale-up, a high level of direction and control is required. Recently, block copolymers (BCP) have attracted much attention as a powerful and very promising tool for creation of nanoscale ordered structures owing to their self-assembling properties. In addition, these systems offer the possibility to fabricate nanostructured composite materials via incorporation of certain nanoadditives (i.e. NPs). The concept is that by selective inclusion of the nanoparticles into one of the blocks of a self-assembling copolymer, the nanoparticles are forced into a defined spatial arrangement determined by the phase morphology of the block copolymer. In present work self-assembling phenomena of block copolymers was exploited to fabricate binary (NP/BCP) and ternary (NP1/NP2/BCP) composites, filled with pre-synthesized nanoparticles of various nature. Polystyrene-block-polyvinylpyridine block copolymers (PS-b-PVP) of various composition and molecular weight were used for fabrication of nanocomposites. The first part of the thesis focuses on fabrication of functional BCP-based composites containing magnetic nanoparticles (MNP), selectively assembled within one of the blocks of BCP matrix. Magnetic nanoparticles (MNPs) were selected among others since, as for today, there is the least number of successful results reported in literature on their selective incorporation into one of the phases of a BCP matrix. From the application point of view fabrication of periodic arrays of “magnetic domains” with periodicity on nanometer scale is also of interest for potential use in high-density magnetic data storage devices. For this purpose, ferrite-type MNP (Fe3O4, CoFe2O4) having apparent affinity toward polyvinylpyridine (PVP) phase were prepared using simple one-pot synthesis. Highly selective nanoparticles segregation into PVP domains of BCP was achieved owing to the presence of sparse stabilizing organic shell on the nanoparticles surface. Importantly, as-prepared MNPs did not require any additional surface modification step to acquire affinity towards PVP phase. Appropriate selection of annealing conditions allowed to produce patterns of nearly perfect degree of lateral order over relatively large surface large area (more than 4 sq µm). The second task of present work was fabrication of ternary NP1/NP2/BCP hybrid composites with two different types of nanoparticles being selectively localized in different microdomains of phase segregated block copolymer matrix. So far as only few studies have been reported on developing of approaches toward ternary composites, creation of alternative and straight forward routes toward such systems is still a challenge. In the frame of this part of present work, silver nanoparticles (AgNPs) covered with polystyrene shell were prepared, with the purpose to be incorporated into polystarene phase of phase separated PS-b-PVP block copolymer matrix. Two different approaches were tested to achieve desired three-component system. First, supposed simple blending of block copolymer and two kinds of nanoparticles having specific affinity toward different blocks of BCP in common solvent. After preparation of MNP/AgNP/BCP composite thin film and subsequent solvent vapour annealing, different domains of microphase segregated PS-b-PVP BCP were filled with different type of nanoparticles. Alternatively, step-wise approach for nanoparticles incorporation was developed and implemented for successful selective nanoparticles incorporation. For this purpose polystyrene stabilized AgNPs (i.e. NP1) were initially mixed with PS-b-PVP BCP to produce composite thin films having nanoparticles selectively located within PS microdomains, while citrate-stabilized second type nanoparticles (i.e NP2) were deposited from their aqueous solutions into PVP domains of AgNP/PS-b-PVP composites. By partition of nanoparticles incorporation procedure into two distinct steps it was also possible to increase effective loading of each type of NPs into BCP matrix.
24

Nanopatterned Phase-Change Materials for High-Speed, Continuous Phase Modulation

Aboujaoude, Andrea E. January 2018 (has links)
No description available.
25

Low-Cost Nanopatterning using Self-Assembled Ceramic Nanoislands

Zimmerman, Lawrence Burr 24 September 2009 (has links)
No description available.
26

Optimisation de jonctions tunnel magnétiques pour STT-MRAM et développement d'un nouveau procédé de nanostructuration de ces jonctions / Engineering of magnetic tunnel junction stacks for improved STT-MRAM performance and development of novel and cost-effective nano-patterning techniques

Chatterjee, Jyotirmoy 29 March 2018 (has links)
Le but de la thèse sera d'étudier la faisabilité d'un nouveau procédé de nanostructuration des jonctions tunnel de dimension sub-30nm récemment imaginé et breveté par Spintec et le LTM et de tester les propriétés des jonctions tunnel obtenus sur les plans structural, magnétique et des propriétés électriques. Une attention particulière sera mise sur la caractérisation des défauts générés en bord de piliers lors de la gravure des jonctions tunnels et l'impact de ces défauts sur les propriétés magnétiques et de transport. Une autre partie de la thèse concerne l'optimisation des propriétés magnétiques et de transport des empilements jonctions tunnel magnétiques en vue d'en améliorer la stabilité thermique, l'amplitude de magnétoresistance tunnel et la facilité de gravure de l'empilement.En particulier l'insertion de nouveaux matériaux réfractaires (W, ) dans les empilements a été étudiée pour améliorer la stabilité de l'empilement lors des recuits à haute température. Des améliorations ont également été apportées pour renforcer la stabilité de la couche de référence de la jonction tunnel lorsque cette dernière est située au dessus de la barrière tunnel. Par ailleurs, une nouvelle couche de couplage antiferromagnétique a été mise au point permettant de réduire significativement l'épaisseur totale de l'empilement et par là même facilitant sa gravure.Tous ces résultats ont été obtenus par des mesures magnétiques et de transport réalisées sur les couches continues et sur des piliers de taille nanométriques. / The first aim of the thesis is to study the feasibility of a new process for nanopatterning of sub-30nm diameter tunnel junctions recently patented by Spintec and LTM and to test the properties of tunnel junctions obtained, from the point of view of magnetic and electrical properties. Particular attention will be paid on the characterization of defects generated at the pillar edges when patterning the tunnel junctions and the impact of these defects on the magnetic and transport properties. Another part of the thesis is focused on improving the magnetic and transport MTJ stacks with higher thermal budget tolerance. As a part of this, new materials (W, etc) were used as cap layer or as a spacer layer in composite free layer of pMTJ stacks. Moreover, different magnetic materials combined with different non-magnetic spacer have been investigated to improve the thermal stability factor of the composite storage layers. Detailed structural characterizations were performed to demonstrate the improvements in magnetic and electrical properties. A new RKKY coupling layer was found which allowed to obtain an extremely thin pMTJ stack by reducing the SAF layer thickness to 3.8nm. Seed lees multilayers with enhanced PMA is necesssary to realize a top-pinned pMTJ stack which is necessary to configure a spin-orbit torque MRAM (SOT-MRAM)stack and double magnetic tunnel junction stacks (DMTJs). A new seed less multilyar with enhanced PMA and subsequently advanced stacks such as conventional-DMTJ, thin-DMT, SOT-MRAM stacks, Multibit memory were realized. Finally, electrical properties patterned memory devices were also studied to correlate with the magnetic properties of thin films.
27

Block Copolymer Lithographyfor Nano-porous Oxide Thin Films

Liu, Yandi January 2018 (has links)
This thesis focuses on employing a new patterning technique called block copolymer lithography to transfer the nano-porous pattern from the polymer template to the underlying oxide thin film. Nano-porous block copolymer films are produced by spin-coating polymer solution on wafers followed by annealing, UV exposure and development processes. Reactive-ion etching is then used to etch the oxide films based on the pattern of polymer template and the polymer is then removed. The obtained oxide microstructure is characterized by SEM, showing a nanomesh of microdomains with the same hole size and density as the initial block copolymer layer. The advantages of block copolymer lithography include uniform nanopatterning, cost efficiency and simple processing. The nano-porous oxide thin films could be used as hard mask for nanopatterning in microelectronics and for energy storage applications. / Denna avhandling fokuserar på användningen av en ny mönstringsteknik som kallas block-sampolymerlitografi som används för att överföra nano-porösa mönster från polymermaller till en underliggande oxidtunnfilm. Nano-porösa blocksampolymerfilmer framställs genom spinbeläggningspolymerlösning på skivor följt av glödgning, UV-exponering och utvecklingsprocesser. Reaktionjon etsning används sedan för att etsa oxidfilmerna baserat på mönstret av polymermaller och därefter blir polymeren avlägsnad. Den erhållna oxidmikrostrukturen karakteriseras av SEM, som visar en nanomesh av mikrodomäner med samma hålstorlek och densitet som det ursprungliga blocksampolymerskiktet. Fördelarna med block-sampolymerlitografi innefattar likformig nanomönstring, kostnadseffektivitet och enkel bearbetning. De nanoporösa oxidtunnfilmerna kan användas som en hard mask för nanomönstring i mikroelektronik och för energilagringsapplikationer.
28

Contrôle de l'organisation moléculaire en 2D et 3D par l’utilisation de liaisons hydrogène, de coordination métallique et d'autres interactions

Duong, Adam 04 1900 (has links)
La stratégie de la tectonique moléculaire a montré durant ces dernières années son utilité dans la construction de nouveaux matériaux. Elle repose sur l’auto-assemblage spontané de molécule dite intelligente appelée tecton. Ces molécules possèdent l’habilité de se reconnaitre entre elles en utilisant diverses interactions intermoléculaires. L'assemblage résultant peut donner lieu à des matériaux moléculaires avec une organisation prévisible. Cette stratégie exige la création de nouveaux tectons, qui sont parfois difficiles à synthétiser et nécessitent dans la plupart des cas de nombreuses étapes de synthèse, ce qui empêche ou limite leur mise en application pratique. De plus, une fois formées, les liaisons unissant le corps central du tecton avec ces groupements de reconnaissance moléculaire ne peuvent plus être rompues, ce qui ne permet pas de remodeler le tecton par une procédure synthétique simple. Afin de contourner ces obstacles, nous proposons d’utiliser une stratégie hybride qui se sert de la coordination métallique pour construire le corps central du tecton, combinée avec l'utilisation des interactions plus faibles pour contrôler l'association. Nous appelons une telle entité métallotecton du fait de la présence du métal. Pour explorer cette stratégie, nous avons construit une série de ligands ditopiques comportant soit une pyridine, une bipyridine ou une phénantroline pour favoriser la coordination métallique, substitués avec des groupements diaminotriazinyles (DAT) pour permettre aux complexes de s'associer par la formation de ponts hydrogène. En plus de la possibilité de créer des métallotectons par coordination, ces ligands ditopiques ont un intérêt intrinsèque en chimie supramoléculaire en tant qu'entités pouvant s'associer en 3D et en 2D. En parallèle à notre étude de la chimie de coordination, nous avons ii examiné l'association des ligands, ainsi que celle des analogues, par la diffraction des rayons-X (XRD) et par la microscopie de balayage à effet tunnel (STM). L'adsorption de ces molécules sur la surface de graphite à l’interface liquide-solide donne lieu à la formation de différents réseaux 2D par un phénomène de nanopatterning. Pour comprendre les détails de l'adsorption moléculaire, nous avons systématiquement comparé l’organisation observée en 2D par STM avec celle favorisée dans les structures 3D déterminées par XRD. Nous avons également simulé l'adsorption par des calculs théoriques. Cette approche intégrée est indispensable pour bien caractériser l’organisation moléculaire en 2D et pour bien comprendre l'origine des préférences observées. Ces études des ligands eux-mêmes pourront donc servir de référence lorsque nous étudierons l'association des métallotectons dérivés des ligands par coordination. Notre travail a démontré que la stratégie combinant la chimie de coordination et la reconnaissance moléculaire est une méthode de construction rapide et efficace pour créer des réseaux supramoléculaires. Nous avons vérifié que la stratégie de la tectonique moléculaire est également efficace pour diriger l'organisation en 3D et en 2D, qui montre souvent une homologie importante. Nous avons trouvé que nos ligands hétérocycliques ont une aptitude inattendue à s’adsorber fortement sur la surface de graphite, créant ainsi des réseaux organisés à l'échelle du nanomètre. L’ensemble de ces résultats promet d’offrir des applications dans plusieurs domaines, dont la catalyse hétérogène et la nanotechnologie. Mots clés : tectonique moléculaire, interactions intermoléculaires, stratégie hybride, coordination métallique, diffraction des rayons-X, microscopie de balayage à effet tunnel, graphite, phénomène de nanopatterning, calculs théoriques, ponts hydrogène, chimie supramoléculaire, ligands hétérocycliques, groupements DAT, catalyse hétérogène, nanotechnologie. / In recent years, molecular tectonics has been a useful strategy in the construction of new materials. It relies on the spontaneous self-assembly of molecules called tectons. These molecules have the ability to recognize themselves using various intermolecular interactions. The resulting assembly can produce molecular materials with predictable organization. This strategy requires the creation of new tectons, which are sometimes difficult to synthesize and require in most cases many synthetic steps, which prevents or limits their practical application. Moreover, once formed, the bonds joining the central core of the tecton with the groups used for molecular recognition cannot be broken, which means that it is not possible to recycle or reform the tecton by simple synthetic procedures. To avoid these obstacles, we propose to use a hybrid strategy that uses metal coordination to build the central core of the tecton, combined with the use of weaker interactions to control the association. We call such entities metallotectons due to the presence of metal. To explore this strategy, we constructed a series of ditopic ligands containing either pyridine, bipyridine or phenanthroline to promote metal coordination, substituted with diaminotriazinyl groups (DAT) to allow inter-complex association by the formation of hydrogen bonds. In addition to the possibility of creating metallotectons by coordination, these ditopic ligands have an intrinsic interest in supramolecular chemistry as entities that can associate in 3D and 2D. In parallel to our study of coordination chemistry, we examined the association of ligands by X-ray diffraction (XRD) and scanning tunneling microscopy (STM). The adsorption of these molecules on the graphite surface at the liquid-solid interface results in the formation of different networks through a process of 2D nanopatterning. To understand the details of iv molecular adsorption, we systematically compared the 2D organization observed STM with the 3D structures determined by XRD. We also simulated the adsorption by theoretical calculations. This integrated approach is essential to characterize the molecular organization in 2D and to understand the origin of the observed preferences. These studies of the ligands themselves may therefore serve as a reference when we study the association of metallotectons derived by ligands coordination. Our work demonstrates that the strategy combining coordination chemistry and molecular recognition is a rapid and an efficient method to create supramolecular networks. We verified that the strategy of molecular tectonics is also effective in leading the organization in 3D and 2D, which often shows a significant homology. We found that our heterocyclic ligands have unexpected ability to adsorb strongly on the graphite surface, creating networks organize in nanoscale. Together, these results provide promising applications in several fields, including heterogeneous catalysis and nanotechnology. Keywords : molecular tectonics, intermolecular interactions, hybrid strategy, metal coordination, X-ray diffraction, scanning tunneling microscopy, graphite, nanopatterning phenomenon, theoretical calculations, hydrogen bonds, supramolecular chemistry, ligands, DAT groups, heterogeneous catalysis, nanotechnology.
29

Contrôle de l'organisation moléculaire en 2D et 3D par l’utilisation de liaisons hydrogène, de coordination métallique et d'autres interactions

Duong, Adam 04 1900 (has links)
La stratégie de la tectonique moléculaire a montré durant ces dernières années son utilité dans la construction de nouveaux matériaux. Elle repose sur l’auto-assemblage spontané de molécule dite intelligente appelée tecton. Ces molécules possèdent l’habilité de se reconnaitre entre elles en utilisant diverses interactions intermoléculaires. L'assemblage résultant peut donner lieu à des matériaux moléculaires avec une organisation prévisible. Cette stratégie exige la création de nouveaux tectons, qui sont parfois difficiles à synthétiser et nécessitent dans la plupart des cas de nombreuses étapes de synthèse, ce qui empêche ou limite leur mise en application pratique. De plus, une fois formées, les liaisons unissant le corps central du tecton avec ces groupements de reconnaissance moléculaire ne peuvent plus être rompues, ce qui ne permet pas de remodeler le tecton par une procédure synthétique simple. Afin de contourner ces obstacles, nous proposons d’utiliser une stratégie hybride qui se sert de la coordination métallique pour construire le corps central du tecton, combinée avec l'utilisation des interactions plus faibles pour contrôler l'association. Nous appelons une telle entité métallotecton du fait de la présence du métal. Pour explorer cette stratégie, nous avons construit une série de ligands ditopiques comportant soit une pyridine, une bipyridine ou une phénantroline pour favoriser la coordination métallique, substitués avec des groupements diaminotriazinyles (DAT) pour permettre aux complexes de s'associer par la formation de ponts hydrogène. En plus de la possibilité de créer des métallotectons par coordination, ces ligands ditopiques ont un intérêt intrinsèque en chimie supramoléculaire en tant qu'entités pouvant s'associer en 3D et en 2D. En parallèle à notre étude de la chimie de coordination, nous avons ii examiné l'association des ligands, ainsi que celle des analogues, par la diffraction des rayons-X (XRD) et par la microscopie de balayage à effet tunnel (STM). L'adsorption de ces molécules sur la surface de graphite à l’interface liquide-solide donne lieu à la formation de différents réseaux 2D par un phénomène de nanopatterning. Pour comprendre les détails de l'adsorption moléculaire, nous avons systématiquement comparé l’organisation observée en 2D par STM avec celle favorisée dans les structures 3D déterminées par XRD. Nous avons également simulé l'adsorption par des calculs théoriques. Cette approche intégrée est indispensable pour bien caractériser l’organisation moléculaire en 2D et pour bien comprendre l'origine des préférences observées. Ces études des ligands eux-mêmes pourront donc servir de référence lorsque nous étudierons l'association des métallotectons dérivés des ligands par coordination. Notre travail a démontré que la stratégie combinant la chimie de coordination et la reconnaissance moléculaire est une méthode de construction rapide et efficace pour créer des réseaux supramoléculaires. Nous avons vérifié que la stratégie de la tectonique moléculaire est également efficace pour diriger l'organisation en 3D et en 2D, qui montre souvent une homologie importante. Nous avons trouvé que nos ligands hétérocycliques ont une aptitude inattendue à s’adsorber fortement sur la surface de graphite, créant ainsi des réseaux organisés à l'échelle du nanomètre. L’ensemble de ces résultats promet d’offrir des applications dans plusieurs domaines, dont la catalyse hétérogène et la nanotechnologie. Mots clés : tectonique moléculaire, interactions intermoléculaires, stratégie hybride, coordination métallique, diffraction des rayons-X, microscopie de balayage à effet tunnel, graphite, phénomène de nanopatterning, calculs théoriques, ponts hydrogène, chimie supramoléculaire, ligands hétérocycliques, groupements DAT, catalyse hétérogène, nanotechnologie. / In recent years, molecular tectonics has been a useful strategy in the construction of new materials. It relies on the spontaneous self-assembly of molecules called tectons. These molecules have the ability to recognize themselves using various intermolecular interactions. The resulting assembly can produce molecular materials with predictable organization. This strategy requires the creation of new tectons, which are sometimes difficult to synthesize and require in most cases many synthetic steps, which prevents or limits their practical application. Moreover, once formed, the bonds joining the central core of the tecton with the groups used for molecular recognition cannot be broken, which means that it is not possible to recycle or reform the tecton by simple synthetic procedures. To avoid these obstacles, we propose to use a hybrid strategy that uses metal coordination to build the central core of the tecton, combined with the use of weaker interactions to control the association. We call such entities metallotectons due to the presence of metal. To explore this strategy, we constructed a series of ditopic ligands containing either pyridine, bipyridine or phenanthroline to promote metal coordination, substituted with diaminotriazinyl groups (DAT) to allow inter-complex association by the formation of hydrogen bonds. In addition to the possibility of creating metallotectons by coordination, these ditopic ligands have an intrinsic interest in supramolecular chemistry as entities that can associate in 3D and 2D. In parallel to our study of coordination chemistry, we examined the association of ligands by X-ray diffraction (XRD) and scanning tunneling microscopy (STM). The adsorption of these molecules on the graphite surface at the liquid-solid interface results in the formation of different networks through a process of 2D nanopatterning. To understand the details of iv molecular adsorption, we systematically compared the 2D organization observed STM with the 3D structures determined by XRD. We also simulated the adsorption by theoretical calculations. This integrated approach is essential to characterize the molecular organization in 2D and to understand the origin of the observed preferences. These studies of the ligands themselves may therefore serve as a reference when we study the association of metallotectons derived by ligands coordination. Our work demonstrates that the strategy combining coordination chemistry and molecular recognition is a rapid and an efficient method to create supramolecular networks. We verified that the strategy of molecular tectonics is also effective in leading the organization in 3D and 2D, which often shows a significant homology. We found that our heterocyclic ligands have unexpected ability to adsorb strongly on the graphite surface, creating networks organize in nanoscale. Together, these results provide promising applications in several fields, including heterogeneous catalysis and nanotechnology. Keywords : molecular tectonics, intermolecular interactions, hybrid strategy, metal coordination, X-ray diffraction, scanning tunneling microscopy, graphite, nanopatterning phenomenon, theoretical calculations, hydrogen bonds, supramolecular chemistry, ligands, DAT groups, heterogeneous catalysis, nanotechnology.

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