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A series of zirconium-based MOFs with acclaimed stability was prepared and their ability to adsorb polyfluorinated pollutants was compared. A novel fluorinated UiO-67 analogue, UiO-67-F2, was synthesised alongside three previously reported materials: UiO-67-NH2, UiO-68-(CF3)2 and UiO-67. The structures were established and confirmed by powder X-Ray diffraction. UiO-67-NH2, UiO-68(CF3)2 and UiO-67-F2 were examined as sorbents for the perfluorinated gas, sulphur hexafluoride (SF₆) from the gaseous phase. The SF₆ uptake of UiO-67-NH2 and UiO-67-F2 at 100 kPa, 293 K, was high (5.54 and 5.24 mmol g ^-1 respectively). UiO-67-F2 exhibited a remarkable perfluorinated octanoic acid (PFOA) uptake of 928 mg_PFOA g ^-1_MOF in an aqueous solution, which far exceeded that of unmodified UiO-67 (872 mg_PFOA g ^-1_MOF at 1 000 mg_PFOA L ^-1_Water PFOA). This study has identified strengths and potential applications of the novel UiO-67-F2 and the impact of fluorine functionalization. The study also offers insight into the structure-property relations of UiO-based MOFs for their use as low-pressure SF6 storage materials and PFAS sorbents intended for water purification under ambient conditions.

Molecular catalysts for water oxidation and other electrochemical transformations have been a focus of significant research over recent decades. Among these, α-[Fe(mcp)L2] complexes stand out as one of the most active non-heme iron-based molecular catalyst for water oxidation. This study investigates how the Fe(II)/Fe(III) redox potential of these catalysts varies with the identity of their labile ligands (L). Using cyclic voltammetry and complementary spectroscopic techniques (UV/Vis, 1H-NMR), we examined how ligands bind to the metal centre. Systematic variation of the labile ligand (L) demonstrated that the catalyst's redox potential in acetonitrile solution strongly depends on ligand identity. By introducing stoichiometric amounts of different anions to the electrolyte, the redox potential was tuned across a 1.5 V potential window.In aqueous solutions, the redox potential depended on both pH and electrolyte anion identity. These dependencies were successfully fitted to a thermodynamic model that was obtained by extending the typical proton-coupled electron transfer square scheme into a cube scheme that incorporates anion binding. The equation derived from this model provides valuable insights into the ligand-binding dynamics at the iron centre under diverse conditions.

Molecular catalysts are attracting interest as drivers of redox reactions for sustainable applications. Through systematic molecular design, they could be engineered to have high selectivity and activity towards a multitude of catalytic reactions. However, as long as they are used in homogeneous setups, they will suffer from inconvenient energy supply, inefficient charge transport and difficulty in separation from reaction products. To be relevant for industrial applications, molecular catalysts must be bound to solid materials in direct contact with the energy source. In this regard, conducting polymers are particularly interesting, as they provide a straightforward means of both surface immobilization and charge transport. In this work, we synthesize and characterize three different metalloporphyrin-functionalized conducting polymers and apply them to catalysis of the hydrogen evolution reaction (HER) and the oxygen reduction reaction (ORR). We show that incorporation of porphyrins into conducting polymers is a reliable immobilization method, that the properties of both the porphyrin units and the polymer backbone are preserved in all systems, and that the polymers provide efficient charge transport to and from the catalytic centers. Nevertheless, we also find that the polymers are negatively affected by intermediates formed during the HER and the ORR. We conclude that the choice of immobilization method has a large impact on the quality of the molecular catalyst, and that the effect of the catalytic cycle on the immobilization matrix must be considered in the molecular design process.