TY  - JOUR
A1  - Ketenoglu, Didem
A1  - Spiekermann, Georg
A1  - Harder, Manuel
A1  - Oz, Erdinc
A1  - Koz, Cevriye
A1  - Yagci, Mehmet C.
A1  - Yilmaz, Eda
A1  - Yin, Zhong
A1  - Sahle, Christoph J.
A1  - Detlefs, Blanka
A1  - Yavas, Hasan
T1  - X-ray Raman spectroscopy of lithium-ion battery electrolyte solutions in a flow cell
JF  - Journal of synchrotron radiation
N2  - The effects of varying LiPF6 salt concentration and the presence of lithium bis(oxalate)borate additive on the electronic structure of commonly used lithium-ion battery electrolyte solvents (ethylene carbonate-dimethyl carbonate and propylene carbonate) have been investigated. X-ray Raman scattering spectroscopy (a non-resonant inelastic X-ray scattering method) was utilized together with a closed-circle flow cell. Carbon and oxygen K-edges provide characteristic information on the electronic structure of the electrolyte solutions, which are sensitive to local chemistry. Higher Li+ ion concentration in the solvent manifests itself as a blue-shift of both the pi* feature in the carbon edge and the carbonyl pi* feature in the oxygen edge. While these oxygen K-edge results agree with previous soft X-ray absorption studies on LiBF4 salt concentration in propylene carbonate, carbon K-edge spectra reveal a shift in energy, which can be explained with differing ionic conductivities of the electrolyte solutions.
KW  - non-resonant inelastic X-ray scattering
KW  - lithium-ion battery electrolyte
KW  - C and O K-edge spectra
Y1  - 2018
U6  - https://doi.org/10.1107/S1600577518001662
SN  - 0909-0495
SN  - 1600-5775
VL  - 25
SP  - 537
EP  - 542
PB  - International Union of Crystallography
CY  - Chester
ER  - 
TY  - JOUR
A1  - Weis, Christopher
A1  - Spiekermann, Georg
A1  - Sternemann, Christian
A1  - Harder, Manuel
A1  - Vanko, Gyorgy
A1  - Cerantola, Valerio
A1  - Sahle, Christoph J.
A1  - Forov, Yury
A1  - Sakrowski, Robin
A1  - Kupenko, Ilya
A1  - Petitgirard, Sylvain
A1  - Yavas, Hasan
A1  - Bressler, Christian
A1  - Gawelda, Wojciech
A1  - Tolan, Metin
A1  - Wilke, Max
T1  - Combining X-ray K beta(1,3), valence-to-core, and X-ray Raman spectroscopy for studying Earth materials at high pressure and temperature
BT  - the case of siderite
JF  - Journal of analytical atomic spectrometry
N2  - X-ray emission and X-ray Raman scattering spectroscopy are powerful tools to investigate the local electronic and atomic structure of high and low Z elements in situ. Notably, these methods can be applied for in situ spectroscopy at high pressure and high temperature using resistively or laser-heated diamond anvil cells in order to achieve thermodynamic conditions which appear in the Earth's interior. We present a setup for combined X-ray emission and X-ray Raman scattering studies at beamline P01 of PETRA III using a portable wavelength-dispersive von Hamos spectrometer together with the permanently installed multiple-analyzer Johann-type spectrometer. The capabilities of this setup are exemplified by investigating the iron spin crossover of siderite FeCO3 up to 49.3 GPa by measuring the Fe M2,3-edge and the Fe Kβ1,3 emission line simultaneously. With this setup, the Fe valence-to-core emission can be detected together with the Kβ1,3 emission line providing complementary information on the sample's electronic structure. By implementing a laser-heating device, we demonstrate the strength of using a von Hamos type spectrometer for spin state mapping at extreme conditions. Finally, we give different examples of low Z elements' absorption edges relevant for application in geoscience that are accessible with the Johann-type XRS spectrometer. With this setup new insights into the spin transition and compression mechanisms of Earth's mantle materials can be obtained of importance for comprehension of the macroscopic physical and chemical properties of the Earth's interior.
Y1  - 2018
U6  - https://doi.org/10.1039/c8ja00247a
SN  - 0267-9477
SN  - 1364-5544
VL  - 34
IS  - 2
SP  - 384
EP  - 393
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Weis, Christopher
A1  - Sternemann, Christian
A1  - Cerantola, Valerio
A1  - Sahle, Christoph J.
A1  - Spiekermann, Georg
A1  - Harder, Manuel
A1  - Forov, Yury
A1  - Kononov, Alexander
A1  - Sakrowski, Robin
A1  - Yavas, Hasan
A1  - Tolan, Metin
A1  - Wilke, Max
T1  - Pressure driven spin transition in siderite and magnesiosiderite single crystals
JF  - Scientific reports
Y1  - 2017
U6  - https://doi.org/10.1038/s41598-017-16733-3
SN  - 2045-2322
VL  - 7
PB  - Nature Publ. Group
CY  - London
ER  -