Analisi dell'attivazione dell'ossigeno moleculare su Cu-MOFs mediante spettroscopia di emission di raggi X

The Direct transition of Methane To Methanol (DMTM) has been a crucial area of research in the past decade. The use of Cu-zeolites as an oxidation catalyst has shown to be effective in converting alkanes to alcohols with high selectivity but low methanol production. However, Cu-based enzymes in nature provide a better methanol yield at ambient condition, albeit they are too fragile for industrial application. The use of Metal-Organic Frameworks (MOFs) could combine the best features of zeolites and enzymatic catalysts. Cu-MOFs have been investigated using X-ray Absorption Near Edge Structure (XANES) measurements at the Cu K-edge, and selective oxidation of alkanes has been observed. However, the light element surrounding the Cu first shell has been a challenge for better understanding the structure. To overcome this issue, during the thesis project X-ray Emission Spectroscopy (XES) has been employed to achieve a better contrast of the light element surrounding the first coordination shell of the Cu center. The data obtained from the combination of XES and HERFDXANES measurements are in agreement with conventional X-ray Absorption Spectra (XAS) and provide complementary information on the different Cu oxidation states and their surrounding environments. The MOFs samples underwent activation cycles through three gases (He, H2, O2), and the resulting data are processed and analyzed using Python scripts. The study provides insights into the process of data collection, analysis, and interpretation using XES and HERFD-XANES measurements on CuMOFs