Implementation of cryogenic tender X-ray HR-XANES spectroscopy at the ACT station of the CAT-ACT beamline at the KIT Light Source

The ACT experimental station of the CAT-ACT wiggler beamline at the Karlsruhe Institute of Technology (KIT) Light Source is dedicated to the investigation of radionuclide materials with radioactivities up to 1000000 times the exemption limit by various speciation techniques applying monochromatic X-rays. In this article, the latest technological developments at the ACT station that enable high-resolution X-ray absorption near-edge structure (HR-XANES) spectroscopy for low radionuclide loading samples are highlighted – encompassing the investigation of actinide elements down to 1 p.p.m. concentration – combined with a cryogenic sample environment reducing beam-induced sample alterations. One important part of this development is a versatile gas tight plexiglass encasement ensuring that all beam paths in the five-analyzer-crystal Johann-type X-ray emission spectrometer run within He atmosphere. The setup enables the easy exchange between different experiments (conventional X-ray absorption fine structure, HR-XANES, high-energy or wide-angle X-ray scattering, tender to hard X-ray spectroscopy) and opens up the possibility for the investigation of environmental samples, such as specimens containing transuranium elements from contaminated land sites or samples from sorption and diffusion experiments to mimic the far field of a breached nuclear waste repository.

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High-energy resolution X-ray absorption and emission spectroscopy reveals insight into unique selectivity of La-based nanoparticles for CO2

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1516192113 ◽

2015 ◽

Vol 112 (52) ◽

pp. 15803-15808 ◽

Cited By ~ 23

Author(s):

Ofer Hirsch ◽

Kristina O. Kvashnina ◽

Li Luo ◽

Martin J. Süess ◽

Pieter Glatzel ◽

...

Keyword(s):

Energy Resolution ◽

Emission Spectroscopy ◽

High Energy ◽

Unit Cell ◽

High Energy Resolution ◽

Electron Configuration ◽

Edge Structure ◽

X Ray ◽

X Ray Absorption

The lanthanum-based materials, due to their layered structure and f-electron configuration, are relevant for electrochemical application. Particularly, La2O2CO3 shows a prominent chemoresistive response to CO2. However, surprisingly less is known about its atomic and electronic structure and electrochemically significant sites and therefore, its structure–functions relationships have yet to be established. Here we determine the position of the different constituents within the unit cell of monoclinic La2O2CO3 and use this information to interpret in situ high-energy resolution fluorescence-detected (HERFD) X-ray absorption near-edge structure (XANES) and valence-to-core X-ray emission spectroscopy (vtc XES). Compared with La(OH)3 or previously known hexagonal La2O2CO3 structures, La in the monoclinic unit cell has a much lower number of neighboring oxygen atoms, which is manifested in the whiteline broadening in XANES spectra. Such a superior sensitivity to subtle changes is given by HERFD method, which is essential for in situ studying of the interaction with CO2. Here, we study La2O2CO3-based sensors in real operando conditions at 250 °C in the presence of oxygen and water vapors. We identify that the distribution of unoccupied La d-states and occupied O p- and La d-states changes during CO2 chemoresistive sensing of La2O2CO3. The correlation between these spectroscopic findings with electrical resistance measurements leads to a more comprehensive understanding of the selective adsorption at La site and may enable the design of new materials for CO2 electrochemical applications.

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Characterization of selenium speciation in selenium-enriched button mushrooms (Agaricus bisporus) and selenized yeasts (dietary supplement) using X-ray absorption near-edge structure (XANES) spectroscopy

Journal of Trace Elements in Medicine and Biology ◽

10.1016/j.jtemb.2018.10.018 ◽

2019 ◽

Vol 51 ◽

pp. 164-168 ◽

Cited By ~ 4

Author(s):

Alexander Prange ◽

Miriam Sari ◽

Susanne von Ameln ◽

Csaba Hajdu ◽

Reinhard Hambitzer ◽

...

Keyword(s):

Dietary Supplement ◽

Agaricus Bisporus ◽

Xanes Spectroscopy ◽

Selenium Speciation ◽

Edge Structure ◽

X Ray ◽

Button Mushrooms ◽

X Ray Absorption

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Study of surface films of crystalline and amorphous overbased sulfonates and sulfurized olefins by X-ray absorption near edge structure (XANES) spectroscopy

Tribology Letters ◽

10.1007/s11249-006-9190-9 ◽

2007 ◽

Vol 26 (2) ◽

pp. 173-180 ◽

Cited By ~ 6

Author(s):

Michael T. Costello ◽

Roberto A. Urrego ◽

Masoud Kasrai

Keyword(s):

Xanes Spectroscopy ◽

Surface Films ◽

Edge Structure ◽

X Ray ◽

X Ray Absorption

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Performance of secondary P-fertilizers in pot experiments analyzed by phosphorus X-ray absorption near-edge structure (XANES) spectroscopy

AMBIO ◽

10.1007/s13280-017-0973-z ◽

2017 ◽

Vol 47 (S1) ◽

pp. 62-72 ◽

Cited By ~ 19

Author(s):

Christian Vogel ◽

Camille Rivard ◽

Verena Wilken ◽

Andreas Muskolus ◽

Christian Adam

Keyword(s):

Xanes Spectroscopy ◽

Edge Structure ◽

X Ray ◽

Pot Experiments ◽

X Ray Absorption ◽

P Fertilizers

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Phosphorus K-edge XANES spectroscopy has probably often underestimated iron oxyhydroxide-bound P in soils

Journal of Synchrotron Radiation ◽

10.1107/s1600577518013334 ◽

2018 ◽

Vol 25 (6) ◽

pp. 1736-1744 ◽

Cited By ~ 5

Author(s):

Jörg Prietzel ◽

Wantana Klysubun

Keyword(s):

Linear Combination ◽

Xanes Spectroscopy ◽

Organic P ◽

Iron Oxyhydroxide ◽

Edge Structure ◽

X Ray ◽

Soil P ◽

P Sorption ◽

Fe Oxyhydroxides ◽

X Ray Absorption

Phosphorus (P) K-edge X-ray absorption near-edge structure (XANES) spectra of orthophosphate (oPO4) bound to soil FeIII minerals (e.g. ferrihydrite, goethite) show a pre-edge signal at 2148–2152 eV. It is unknown whether organic P bound to FeIII oxyhydroxides also show this feature. Otherwise, Fe-bound soil P may be underestimated by P K-edge XANES spectroscopy, because a large portion of Fe oxyhydroxide-bound P in soils is organic P. K-edge XANES spectra were obtained for different organic P compounds present in soils [inositol hexaphosphate (IHP), glucose-6-phosphate (G6P), adenosine triphosphate (ATP)] after sorption to ferrihydrite or goethite and compared with spectra of oPO4 adsorbed to these minerals. P sorption to ferrihydrite increased in the sequence IHP ≪ G6P < oPO4 < ATP. P sorption to goethite increased in the sequence G6P < oPO4 ≪ ATP = IHP. Pre-edge signals in P K-edge XANES spectra of organic P adsorbed to Fe oxyhydroxides were markedly smaller compared with those of oPO4 adsorbed to these minerals and absent for FeIII oxyhydroxide-bound ATP as well as goethite-bound IHP. Linear combination fitting (LCF) performed on spectra of IHP, G6P or ATP adsorbed to ferrihydrite or goethite, using only spectra of FeIII oxyhydroxide-bound oPO4 as reference compounds for Fe-bound P, erroneously assigned >93% (ferrihydrite) or >41% (goethite) of Fe-bound P to non-Fe-bound P species. Inclusion of FeIII oxyhydroxide-bound IHP as reference compounds markedly increased the recovery of oxyhydroxide-bound organic P. Thus, Fe-bound soil P has probably often been underestimated by LCF in soil XANES studies where IHP adsorbed to ferrihydrite and to goethite were not included as reference compounds.

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