9th Conference on Industrial Computed Tomography, Padova, Italy (iCT 2019)

Synchrotron based absorption edge tomographyfor the analysis of 3D printed polymer embedded MOF

Christian Gollwitzer1, Philipp Scholz1, Alexander Ulbricht1, Yogita Joshi1, Steffen Weidner1

1Bundesanstalt für Materialforschung und -prüfung, Unter den Eichen 87, 12205 Berlin, Germanye-mail: christian.gollwitzer@bam.de, philipp.scholz@bam.de, alexander.ulbricht@bam.de,

steffen.weidner@bam.de

AbstractAbsorption edge tomography (AET), also known as differential tomography at absorption edges, is amethod which exploits the sudden change of the attenuation coefficient, when the photon energy crossesthe absorption edge of an element [1]. Synchrotron radiation is the best source for absorption edge tomo-graphy, because of its small bandwidth, high intensity and easily adjustable photon energy [2]. The syn-chrotron beamline BAMline at the synchrotron radiation facility BESSY II in Berlin, which is operatedby the Bundesanstalt für Materialforschung und -prüfung (BAM), provides a monochromatized beam in aphoton energy range from 5 keV up to 80 keV with a bandwidth of 2%, when the double multilayer mono-chromator is used [3]. Together with the microtomography setup, this enables differential tomography withsubmicron resolution at the K edge of the elements [4] from chromium up to the lanthanides, and up touranium, when the L edges are used as well.In this work, mechanochemically synthesized metal-organic framework (MOF) material HKUST-1 in com-bination with acrylonitrile-butadiene styrene (ABS) polymer was used to form a polymer MOF compositematerial by a simple extruder. This composite filament was used for 3D printing. Absorption edge tomo-graphy facilitated the evaluation of the 3D distribution of the MOF material both in the filament and theresultant printed sample up to µm resolution. Our very first data indicate, that HKUST-1 is mainly homo-geneously dispersed in both polymer bulk materials. In addition, a few clusters having significantly higherCu concentration were found. AET in combination with data fusion also allows for the calculation of theMOF amount located on the external polymer surface.

Keywords: Absorption edge tomography, metal organic framework, synchrotron CT,additive manufacturing

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