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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 mgPFOA g -1MOF in an aqueous solution, which far exceeded that of unmodified UiO-67 (872 mgPFOA g -1MOF at 1 000 mgPFOA L -1Water 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.

Efficient molecular electrocatalysts are a vital part of the ongoing transition towards sustainable fuel production and away from expensive traditional noble metal catalysts. Molecular catalysts can be synthesized from earth-abundant elements and have well-defined catalytic sites [1], but are associated with poor electronic connection and impractical product separation in homogeneous setups [1-2]. We have synthesized and characterized a conducting redox polymer [3–4] consisting of a conjugated EDOT-based polymer functionalized with free base porphyrins. The polymer allows for simple surface immobilization, a higher number of catalytic units than a monolayer, and continuous charge transport to and from the redox centers of the porphyrins over a large potential window. The porphyrins are aromatic macrocyclic ligands with a rich redox chemistry that can be metallated with a wide variety of metals. Through substitution and metalation, the catalytic selectivity of these redox non-innocent compounds can be tuned towards environmentally beneficial redox reactions, such as solar-powered hydrogen evolution or CO2 reduction. Through electrochemical analysis, we have established that the individual properties of the system building-blocks are preserved, that the polymer improves porphyrin reaction kinetics, that the porphyrins are efficient conduits for electron transfer, and that the porphyrin pendant units can be metallated before or after polymerization. The system should thus be regarded as a stable fundamental platform that through appropriate molecular fine-tuning can be can be used for heterogeneous catalysis of environmentally beneficial redox reactions. References [1] A. Corma, H. Garcia, Top. Catal. 48 (2008) 8. [2] W. Herrmann, C. Kohlpaintner, Angew. Chem. Int. Ed. Engl. 32 (1993) 1524. [3] M. Sterby, R. Emanuelsson, F. Mamedov, M. Strømme, M. Sjödin, Electrochim. Acta. 308 (2019) 277. [4] G. Zotti, A. Berlin, G. Pagani, G. Schiavon, S. Zecchin, Adv. Mater. 7 (199

Electrocatalysts play an essential role in converting electrical energy into fuel and vice versa. A wide variety of well defined molecular catalysts have been developed to catalyze key reactions like water oxidation, proton reduction, carbon dioxide reduction etc..[1] Immobilizing molecular catalyst on electrode surface combines the benefits of having a well defined catalytic center with the benefits of heterogeneous catalysts such as efficient electronic connection between the electrode and the catalytic center.[1] Having surface constrained catalytic sites and using electrochemical methods enables the investigation of catalytic reactions at various potentials and the determination of kinetic thermodynamic parameters without mass transport limitations.[1] The immobilization of molecular catalysts on an electrode surface can be achieved by incorporating them in a conducting redox polymer.[1-3] These polymers consist of a conducting polymer backbone, such as polythiophene, and covalently bound redox active pendant groups. In this poster we present the synthesis and electrochemical characterization of conducting redox polymers bearing molecular catalysts as pendant groups. Functionalized derivatives of molecular catalysts are coupled with monomeric or trimeric units of 3,4-ethylenedioxythiophene (EDOT) or 3,4-propylenedioxythiophene (ProDOT). Subsequent electro polymerization yields functionalized electrodes which are investigated by cyclic voltammetry as well as a variety of in situ methods such as UV-vis spectroscopy, and conductance measurements.[4] References [1] R. M. Bullock et al., Chem. Eur. J. 23 (2017) 7626–7641. [2] L. Wang et al. Chem., Commun. 51 (2015) 7883–7886. [3] D. Curran et al., Chem. Soc. Rev. 20 (1991) 391. [4] M. Sterby et al., Electrochimica Acta 308 (2019) 277–284.