Structural, thermal and functional characterization of metal-organic frameworks containing poly(pyrazolates)-based ligands for carbon dioxide adsorption

The dissertation proposes a comprehensive and systematic study of five new families of bis(pyrazolate) metal-organic frameworks (MOFs) for post-combustion CO2 capture and sequestration (CCS). Chapter I introduces the reader to the renowned problem of global warming, with a special focus on the role of CO2 and the different technologies for post-combustion CCS. MOFs state of the art in CO2 adsorption and the essential properties they should possess to be efficient in this application conclude the Chapter. Chapter II, after an overview on the use of pyrazolate-based MOFs, collects the syntheses of the studied compounds. The structural and thermal characterizations are reported in Chapter III. Chapter IV discusses the textural and adsorption properties, focusing on the influence of the different ligand functionalization. A comparison between the studied MOFs and the literature ones is then reported. Finally, starting from the most performing bis(pyrazolates) in terms of CO2 capacity and affinity, a series of mixed-ligand MOFs (MIXMOFs) is presented to further elucidate the role of linker functionalization in CO2 adsorption. MIXMOFs syntheses and full solid-state characterization are collected in Chapter V together with their CO2 adsorption capacity, affinity and selectivity. MIXMOFs performances are then compared to those of state-of-the-art materials developed for CO2 capture.