Synthesis of metal-organic frameworks for energetic applications ; Synthèse de matériaux de type metal-organic frameworks pour l'énergétique

This thesis is dedicated to the study of the energetic behaviors and performances of Lyophobic Heterogeneous Systems (LHSs) in intrusion–extrusion experiments. In this work, LHSs involve Metal-Organic Frameworks (MOFs) as porous materials and water or aqueous electrolyte solutions as non-wetting liquids. Upon the application of an external pressure to a LHS, the applied mechanical energy is converted into interfacial energy. When the external pressure is released, the LHS can either completely restore or (partially or completely) dissipate the stored mechanical energy, thereby behaving as a spring, shock-absorber, or bumper, respectively.This work aims at defining the effects of various parameters, such as the nature of the non-wetting liquid, the material’s topology and the linker substitution, on the energetic behaviors and performances of LHSs in order to design perfect systems for practical applications. As an example, the presence of an electron donating or withdrawing group on the linker in SOD-type MOFs is shown to enable tuning the energetic behavior of the LHS when using aqueous electrolyte solutions.Moreover, the energetic performances of two hydrophobic MOF materials, MAF-6 and ZIF-71 of RHO topology are also studied. The “MAF-6‒water” and “MAF-6‒ or ZIF-71‒LiCl 20 M” systems display mainly bumper behavior, as the supplied mechanical energy is principally absorbed by the materials when undergoing an irreversible phase transformation. Different scenarios, experimentally supported, explain these results. Finally, the optimization of the syntheses of promising MOF materials, their full characterization and the study of their energetic performances are described. ; Cette thèse est dédiée à l'étude des performances énergétiques de systèmes hétérogènes lyophobes (SHLs) par des expériences d'intrusion-extrusion. Dans ce travail, les SHLs sont constitués de matériaux de type Metal-Organic Framework (MOF) en tant que solide poreux et d'eau ou de solution aqueuse d’électrolyte comme liquide non mouillant. Lors ...