Exploring the tunability of trimetallic mixed-metal nodes in PCN250 metal-organic framework for methane to methanol oxidation

A great challenge in modern catalysis concerns the C-H bond activation for the valorisation of methane. We recently observed (exp.CH6110) the activity of MIL-100(Fe) metal organic framework (MOF) in the selective oxidation of methane to methanol (MTM) in mild conditions. A recent theoretical work as also shown that a similar MOF, named PCN250, built upon the same trimetallic Fe-based nodes, if isolated with mixed metals (Fe/Cr), is predicted to possess lower barriers energy for the N2O and C−H bond activation. Many questions remain open, such as the electronic/structural properties of the active intermediate and the possible cooperation of Cr during the MTM oxidation. Indeed, we here propose a combined in situ XAS/XES study, targeting the redox of Fe and Cr sites during the whole catalytic cycle to get a deep understanding of the active sites (Fe/Cr or both?), of the reactive intermediates and of the possible cooperation of both metals during MTM oxidation reaction.