In Situ EXAFS Study of Sr Adsorption on TiO2(110) under High Ionic Strength Wastewater Conditions

In order to provide important details concerning the adsorption reactions of Sr, batch reactions and a set of both ex situ and in situ Grazing Incidence X-ray Absorption Fine Structure (GIXAFS) adsorption experiments were completed on powdered TiO2 and on rutile(110), both reacted with either SrCl2 or SrCO3 solutions. TiO2 sorption capacity for strontium (Sr) ranges from 550 ppm (SrCl2 solutions, second order kinetics) to 1400 ppm (SrCO3 solutions, first order kinetics), respectively, and is rapid. Sr adsorption decreased as a function of chloride concentration but significantly increased as carbonate concentrations increased. In the presence of carbonate, the ability of TiO2 to remove Sr from the solution increases by a factor of ~4 due to rapid epitaxial surface precipitation of an SrCO3 thin film, which registers itself on the rutile(110) surface as a strontianite-like phase (d-spacing 2.8 Å). Extended X-ray Absorption Fine Structure (EXAFS) results suggest the initial attachment is via tetradental inner-sphere Sr adsorption. Moreover, adsorbates from concentrated SrCl2 solutions contain carbonate and hydroxyl species, which results in both inner- and outer-sphere adsorbates and explains the reduced Sr adsorption in these systems. These results not only provide new insights into Sr kinetics and adsorption on TiO2 but also provide valuable information concerning potential improvements in effluent water treatment models and are pertinent in developing treatment methods for rutile-coated structural materials within nuclear power plants.

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Kinetic analysis of Ag particle redispersion into ZSM-5 in the presence of coke using in situ XAFS

Catalysis Science & Technology ◽

10.1039/d0cy01989e ◽

2021 ◽

Author(s):

Kazumasa Murata ◽

Junya Ohyama ◽

Atsushi Satsuma

Keyword(s):

Fine Structure ◽

Kinetic Analysis ◽

X Ray ◽

Xafs Spectroscopy ◽

Absorption Fine ◽

Ag Particles ◽

In Situ Xafs ◽

Ag Particle ◽

X Ray Absorption

In the present study, the redispersion behavior of Ag particles on ZSM-5 in the presence of coke was observed using in situ X-ray absorption fine structure (XAFS) spectroscopy.

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Backbonding contributions to small molecule chemisorption in a metal–organic framework with open copper(i) centers

Chemical Science ◽

10.1039/d0sc06038k ◽

2021 ◽

Author(s):

Gregory M. Su ◽

Han Wang ◽

Brandon R. Barnett ◽

Jeffrey R. Long ◽

David Prendergast ◽

...

Keyword(s):

Fine Structure ◽

Small Molecule ◽

Metal Organic Framework ◽

X Ray ◽

Metal Site ◽

Absorption Fine ◽

Metal Organic ◽

X Ray Absorption ◽

Organic Framework

In situ near edge X-ray absorption fine structure spectroscopy directly probes unoccupied states associated with backbonding interactions between the open metal site in a metal–organic framework and various small molecule guests.

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Electronic Structures of Crystalline and Aqueous Solutions of LiBr, NaBr, KBr, and KBrO3: In Situ Br L-Edge Near-edge X-ray Absorption Fine Structure

The Journal of Physical Chemistry B ◽

10.1021/jp0304327 ◽

2003 ◽

Vol 107 (46) ◽

pp. 12562-12565 ◽

Cited By ~ 5

Author(s):

Shuji Matsuo ◽

Ponnusamy Nachimuthu ◽

Dennis W. Lindle ◽

Hisanobu Wakita ◽

Rupert C. C. Perera

Keyword(s):

Fine Structure ◽

Aqueous Solutions ◽

Electronic Structures ◽

X Ray ◽

Absorption Fine ◽

X Ray Absorption

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Extended X-ray Absorption Fine Structure Studies of GaN Epilayers Doped in situ with Er and Eu During Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-798-y5.10 ◽

2003 ◽

Vol 798 ◽

Cited By ~ 3

Author(s):

V. Katchkanov ◽

J. F. W. Mosselmans ◽

S. Dalmasso ◽

K. P. O'Donnell ◽

R. W. Martin ◽

...

Keyword(s):

Fine Structure ◽

Rare Earth ◽

Molecular Beam Epitaxy ◽

Local Structure ◽

Molecular Beam ◽

X Ray ◽

Absorption Fine ◽

X Ray Absorption ◽

The Eu

ABSTRACTThe local structure around Er and Eu atoms introduced into GaN epilayers was studied by means of Extended X-ray Absorption Fine Structure above the appropriate rare-earth X-ray absorption edge. The samples were doped in situ during growth by Molecular Beam Epitaxy. The formation of ErN clusters was found in samples with high average Er concentrations of 32±6% and 12.4±0.8%, estimated by Wavelength Dispersive X-ray analysis. When the average Er concentration is decreased to 6.0±0.2%, 1.6±0.2% and 0.17±0.02%, Er is found in localised clusters of ErGaN phase with high local Er content. Similar behaviour is observed for Eu-doped samples. For an average Eu concentration of 30.5±0.5% clusters of pure EuN occur. Decreasing the Eu concentration to 10.4±0.5% leads to EuGaN clusters with high local Eu content. However, for a sample with an Eu concentration of 14.2±0.5% clustering of Eu was not observed.

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Temperature-dependent structural changes of [Bmim]FeCl4 magnetic ionic liquid characterized by an in-situ X-ray absorption fine structure

Chinese Chemical Letters ◽

10.1016/j.cclet.2019.05.028 ◽

2020 ◽

Vol 31 (3) ◽

pp. 801-804

Author(s):

Fangling Jiang ◽

Hao Peng ◽

Cheng Li ◽

Haiying Fu ◽

Guozhong Wu

Keyword(s):

Ionic Liquid ◽

Fine Structure ◽

Structural Changes ◽

Temperature Dependent ◽

X Ray ◽

Absorption Fine ◽

Magnetic Ionic Liquid ◽

X Ray Absorption

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Fluorescence Extended X-Ray Absorption Fine Structure Study on Local Structures of Rare-Earth-Doped InGaGdN

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1133.429 ◽

2016 ◽

Vol 1133 ◽

pp. 429-433

Author(s):

Siti Nooraya Mohd Tawil ◽

Shuichi Emura ◽

Daivasigamani Krishnamurthy ◽

Hajime Asahi

Keyword(s):

Fine Structure ◽

Rare Earth ◽

Nearest Neighbor ◽

Structure Study ◽

Edge Structure ◽

X Ray ◽

Local Structures ◽

Absorption Fine ◽

X Ray Absorption

Local structures around gadolinium atoms in rare-earth (RE)-doped InGaGdN thin films were studied by means of fluorescence extended X-ray absorption fine structure (EXAFS) measured at the Gd LIII-edges. The samples were doped with Gd in-situ during growth by plasma-assisted molecular beam epitaxy (PAMBE). Gd LIII-edge EXAFS signal from the GaGdN, GdN and Gd foil were also measured as reference. The X-ray absorption near edge structure (XANES) spectra around Gd LIII absorption edge of InGaGdN samples observed at room temperature indicated the enhancement of intensities with the increase of Gd composition. Further EXAFS analysis inferred that the Gd atoms in InGaN were surrounded by similar atomic shells as in the case of GaGdN with the evidence indicating majority of Gd atoms substituted into Ga sites of InGaGdN. A slight elongation of bond length for the 2nd nearest-neighbor (Gd–Ga) of sample with higher Gd concentration was also observed.

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