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A newly developed EXAFS setup is presented. It enables both time- and spatially resolved EXAFS information simul-taneously in a single shot. First tests of this setup were performed at the BAMline @ BESSY-II (Berlin, Germany). A primary broadband beam generated by a filter/X-ray-mirror combination passes through the sample and is then dif-fracted by a convexly bent Si (111) crystal. This results in a divergent beam which is collected by an area sensitive detector, in a θ-2θ-geometry. Beside tests on metal foils the first in situ measurements were successfully carried out. The case-study deals with research on Zn-based Metal-Organic-Frameworks (MOF) with medical/pharmaceutical applications. This hot topic of MOFs research concerns drug delivery and encapsulation of therapeutically relevant proteins (e.g. BSA). Questions like how does a certain protein influences the coordination of Zn can be answered with this new setup. We were able to track structural changes within a 1s time resolution.
In this work, a new setup for dispersive XAFS measurements is presented. This reproducible and scanningfree setup yields both time- and laterally-resolved XAFS experiments in a ‘single-shot’. It allows a straightforward adjustment for probing different elements covering many relevant applications in materials science. An incoming energetic broadband beam is diffracted by a Si (111) crystal after passing through the sample and collected by an area sensitive detector. Depending on the energy range of the incoming beam, XANES and/or EXAFS spectra can be recorded with a time resolution down to 1 s. The feasibility of this setup was demonstrated at the BAMline at BESSY II (Berlin, Germany) with reference Fe and Cu foils and the results are hereby presented and discussed. Additionally, an application where time resolution on the second scale is required is briefly evaluated. The presented example concerns studying early stages of zinc(II)2-methylimidazolate (ZIF-8) crystallization. This is particularly important for biomedical applications.