Dans cette thèse nous avons étudié la mise en forme de matériaux carbonés par des méthodes électrochimiques pour des applications dans les domaines des capteurs et de l’énergie. Dans la première partie, l’électrochimie bipolaire, qui permet de réaliser des réactions électrochimiques sur un objet conducteur présent dans une solution et soumise à un champ électrique, a été utilisée pour générer des objets de type Janus. Ces objets asymétriques ont été modifiés à une extrémité par du poly(N-isopropylacrylamide (pNIPAM), un hydrogel sensible à la température, et par une peinture électrophorétique à l’autre extrémité. En contrôlant l’intensité du champ électrique ainsi que son temps d’application il a été possible de varier la longueur ainsi que l’épaisseur de l’hydrogel. Ces objets sensibles à la température, émettant de la lumière, ont des applications potentielles dans le domaine des capteurs ou dans le milieu médical.Dans la seconde partie, la mise en forme de carbone poreux pour des applications électrochimiques a été étudiée. La carbonisation de polymères contenant du zinc a été utilisé pour synthétiser du carbone micro/mésoporeux possédant ainsi une grande surface spécifique. Les polymères contenant du zinc ont été préparés à partir de différents types de ligands d’acide dicarboxylique par une méthode solvothermique. Ils ont ensuite été carbonisés pour obtenir des matériaux poreux avec des caractéristiques et des propriétés particulières. Ils ont été utilisés comme matériaux d’électrode pour des supercondensateurs, montrant des capacités élevées. De plus ils possèdent également une activité électrocatalytique à la réaction de réduction de l’oxygène. / In this thesis, the design of advanced carbon materials via electrochemical techniques and for electrochemical applications have been studied. In the first part, the concept of bipolar electrochemistry, which allows carrying out electrochemical reactions on a free-standing conductive object in an electric field, was employed to generate Janus-type objects. These objects are modified with a thermoresponsive hydrogel of poly(N-isopropylacrylamide) (pNIPAM) on one side and an electrophoretic deposition paint (EDP) on the other side. The results show that the length and the thickness of the hydrogel can be controlled by varying the electric field and the time of the experiment. The concept can be further generalized to other micro- and nanometer-sized objects, thus opening up perspectives for various applications.In the second part, the design of porous carbon structures for electrochemical applications was studied. The direct carbonization of non-porous zinc containing polymers was used to synthesize micro/mesoporous carbons with high surface area, pore volume. Non-porous zinc containing polymers with various types of dicarboxylic acid ligands prepared by solvothermal method were used as templates and starting materials. After carbonization porous carbons with various characteristics and properties were obtained. The synthesized porous carbon samples showed good electrochemical performance with high capacitance values. In addition, the derived materials exhibit excellent electrocatalytic activity with respect to the oxygen reduction reaction (ORR).

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Multiphase systems provide an opportunity to develop both novel processing methods and create advanced materials through combining the properties of dissimilar phases in a synergistic manner. In this work, we detail the halogenation of poly(ether ether ketone) (PEEK) through both solution-state and gel-state functionalization methods. The multiphase gel-state chemistry restricts functionalization to the amorphous regions of the semi-crystalline parent homopolymer and generates a copolymer with a blocky microstructure. Solution-state functionalization yields random copolymers which provide matched sets to the blocky analogs for fundamental investigations into the effects of polymer microstructure on material properties. Halogenating PEEK using N-halosuccinimides allows for direct installation of pendant halogens along the polymer backbone with facile control of halogen identity. For both bromination and iodination, blocky halogenation of PEEK provides faster crystallization kinetics, higher glass transition (Tg) and melting temperatures as well as superior crystallizability than random halogenation. When comparing halogen identity, increasing halogen size results in increased Tgs, decreased backbone planarity, and for copolymers with blocky microstructures, an earlier onset of phase separation. Increasing halogen size also results in decreased crystallizability and crystallization kinetics, however, these deleterious effects are mitigated in blocky microstructures due to colocalization of the pristine repeat units. Iodination also results in greater flame resistance than bromination for PEEK-based copolymers, and preserved crystallizability allows for the generation of flame retardant aerogels. Direct halogenation of PEEK in the gel-state also provided a reactive microstructural template for subsequent functionalization. Through the use of copper mediated cross-coupling chemistries, the aryl halide functionalities were leveraged to decorate the polymer backbone with pendant perfluoroalkyl chains. The blocky perfluoro alkyl PEEK demonstrated preserved crystallizability and serves as a candidate for compatibilization of poly(tetrafluoroethylene)-PEEK polymer blends. Superacid-modified PEEK was synthesized through a similar methodology and demonstrated over 50,000% increased hygroscopicity relative to the parent homopolymer, and exhibited preserved crystallizability. Multiphase systems were also designed to additively manufacture reinforced elastomers through vat photopolymerization using a degradable scaffold approach that challenged the current paradigm that the scaffold only serves as a geometrical template in vat photopolymerization. The scaffold crosslinks were cleaved through a reactive extraction process that liberated the glassy photopolymer backbone and resulted in over 200% increased ultimate strain and 50% increased ultimate stress relative to a control that was subjected to a neutral extraction. Lastly, thermoresponsive micellar ligands were synthesized as a multiphase approach to environmental remediation of metal-contaminated aqueous systems. / Doctor of Philosophy / Multiphase systems, such as a mixture of oil and water, are of great interest due to their ability to exhibit a multitude of properties from one material. Minimizing the size of the phases, through a technique called compatibilization, often improves the properties of the material. A common example is salad dressing, where the oil phase is compartmentalized into microscopic particles using surface-active molecules known as surfactants. Surfactants, also known as amphiphiles, partition to the interface between different phases due to the surfactants being comprised of dissimilar molecular constituents. One way to generate polymeric amphiphiles, where a polymer is a large molecule comprised of a molecular chain of repeating units, is through synthesizing block copolymers. Block copolymers have blocks of different constituents that are colocalized through covalent bonds in the polymer backbone and often exhibit phase separated structures, allowing for enhanced transport properties such as is seen in membranes. Using semi-crystalline polymers in membranes allows for enhanced mechanical integrity, as the crystallites act as physical crosslinks, or tie points, similar to the knots in a 3D rope ladder. These molecular knots limit the distance that the linear segments of the rope ladder can stretch, which in membranes leads to reduced swelling and increased mechanical performance. In this work we use semi-crystalline polymers to generate blocky copolymers through the use of halogenation. Halogenation installs halogen moieties as pendant groups on the polymer backbone, which can then by used as a chemical handle for subsequent reactions to further incorporate functionality into the copolymer and achieve desired properties such as proton (hydrogen nuclei) transport in fuel cell membranes. Halogenation also allows for the generation of blocky semi-crystalline copolymers for compatibilizing polymer blends of materials like poly(tetrafluoroethylene) and poly(ether ether ketone). Also in this work, we discuss the additive manufacturing of mechanically reinforced elastomers. An elastomer is another type of crosslinked network, and a mechanically reinforced elastomer can be through of as a 3D rope ladder where some of the linear segments of rope are replaced with steel bars, thus increasing the amount of work required to deform the network. The last multiphase systems discussed are similar to salad dressing, where there is a continuous water phase and a microscopic particle phase. The microscopic particles in this work are amphiphilic block copolymers that change their solubility in water with temperature and also have functionalities that should allow for the binding of metals from water-based systems.

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