Investigando la flessibilità dei metal-organic frameworks fluorurati per la cattura di anidride carbonica

doMino project has been developed with the intention of using fluorinated, porous and flexible materials, like MOFs, as inorganic fillers for a new generation of Mixed Matrix Membrane (MMMs) for the separation and capture of CO2. In this thesis work, two different fluorinated families of MOFs (MIL140(Ce) and MIL-53(Al)) have been studied and deeply characterized in order to evaluate their CO2 adsorption capacity and their possible utilization as fillers for MMMs applications. MIL-53(Al) has been synthesized and compared with the per-fluorinated MIL-53(Al). It was then discovered that the presence of four fluorine atoms is able to induce the transition from np to lp at ca.473 K. Different behaviour has been showed on the famous MIL-53(Al) in which no phase transition occurs at high temperatures, except the transition induced by the water desorption. F4-CeMIL140, F3-CeMIL140 and F4+F3-CeMIL140 samples synthesized by UniPI, were deeply characterized in order to evaluate their CO2 adsorption capacity. Thanks to the obtained results, it is possible to say that the presence of four fluorine atoms on the phenyl ring in the CeMIL framework is mandatory, even at lower concentrations, in order to increase the affinity with the CO2 molecules and induce the phase transition in a low-pressure range. In conclusion, further investigation and a deeper characterization will be made by changing the number of fluorine atoms in MIL-53(Al) framework in order to evaluate if the thermally induced phase transition, able to tune the pore size, will be still present. The synthesis of different mixed ligands will continue for CeMIL140, in which four fluorine atoms will be always present, even at smaller concentration, while the other portion could be formed by two or even one fluorine atoms. The materials characterized and presented in this Thesis will surely be tested as porous filler for MMMs by Consiglio Nazionale delle Ricerche-Istituto per la Tecnologia delle Membrane (CNR-ITM) for CO2 separation processes, being the main objective of doMino.