Interaction of Niobium with Polycrystalline Palladium Surface. X-ray Photoemission Study

2008 ◽  
Vol 73 (10) ◽  
pp. 1314-1326
Author(s):  
Ivan Jirka ◽  
Zdeněk Bastl
Keyword(s):  
Photoelectron Spectroscopy ◽  
Three Dimensional ◽  
Binding Energies ◽  
Growth Mode ◽  
X Ray ◽  
Line Shapes ◽  
Level Lines ◽  
Pd Alloy ◽  
Palladium Surface ◽  
Photoemission Study

Evolution of niobium-palladium (Nb-Pd) interface alloy prepared by in situ Nb deposition on highly defect polycrystalline Pd surface at room temperature has been investigated using X-ray photoelectron spectroscopy. The binding energies of the Nb 3d5/2 and Pd 3d5/2 core-level lines and their line shapes and the kinetic energies and shapes of Pd M4,5N4,5N4,5 Auger spectrum have been used to characterize the Nb-Pd system. A two-step growth mode of the Nb adlayer has been observed: a two-dimensional (2D)-like growth in a submonolayer Nb concentration region and three-dimensional (3D) intermixing of Nb and Pd atoms at Nb loadings above the monolayer coverage. The latter growth mode resulted in appearance of rather homogeneous Nb-Pd alloy phase.

Growth Mode at the Ge/(1102) Sapphire Interface

1989 ◽  
Vol 159 ◽  
Author(s):  
Geoffrey P. Malafsky
Keyword(s):  
Binding Energy ◽  
Photoelectron Spectroscopy ◽  
Three Dimensional ◽  
Growth Mode ◽  
Relative Fraction ◽  
X Ray ◽  
Bonding State

ABSTRACTThe growth mode of Ge on the (1102) surface of sapphire is explored with X-ray photoelectron spectroscopy. Ge exists in two bonding states at the interface, Ge-Ge and Ge-sapphire. Ge forms islands at submonolayer coverage for deposition temperatures of 25°C and 625°C. The formation of the islands is revealed by the rapid increase in the relative fraction of the Ge-Ge bonding state for Ge coverage less than 1 ML. The shift in the Ge-Ge peak binding energy to the bulk Ge value at less than i ML suggests that the islands are three dimensional for deposition at 625°C.

scholarly journals Switching adsorption and growth behavior of ultrathin [C2C1Im][OTf] films on Au(111) by Pd deposition

2016 ◽  
Vol 18 (36) ◽  
pp. 25143-25150 ◽  
Author(s):  
F. Rietzler ◽  
B. May ◽  
H.-P. Steinrück ◽  
F. Maier
Keyword(s):  
Ionic Liquid ◽  
Photoelectron Spectroscopy ◽  
Three Dimensional ◽  
Liquid Films ◽  
Growth Behavior ◽  
Growth Mode ◽  
Two Dimensional ◽  
X Ray ◽  
Dimensional Growth

In vacuo deposition of ultrathin ionic liquid films combined with angle-resolved X-ray photoelectron spectroscopy demonstrates that the initial three-dimensional growth mode of [C2C1Im][OTf] deposited onto the bare Au(111) surface can be switched to two-dimensional growth by adding submonolayer amounts of Pd.

Characterizing the Thermomechanical Degradation of a Filled Elastomer by Morphology and X Ray Photoelectron Spectroscopy

2001 ◽  
Vol 702 ◽  
Author(s):  
Giovanni F Crosta ◽  
Art J Nelson ◽  
Marina C Camatini
Keyword(s):  
Photoelectron Spectroscopy ◽  
Intrinsic Property ◽  
Binding Energies ◽  
Structural Domain ◽  
X Ray ◽  
Vulcanized Rubber ◽  
A Value ◽  
Debris Particles ◽  
Morphological Descriptor ◽  
Microscopy Images

ABSTRACTThree types of debris particles, denoted by L2, H2 and K3 respectively, originated from the abrasion of silica-filled, vulcanized rubber under different test conditions (severity) were analyzed and compared. The structural fractal dimension, DFS, of the particle perimeter was chosen as a morphological descriptor (but not necessarily as an intrinsic property of the fractured material !). Said dimension was estimated by processing light microscopy images. A value of the morphological threshold, TST, which separates the textural from the structural domain in the RICHARDSON plot was determined in order to maximize discrimination between the three particle types and rank them by increasing values of DFS. Particles from the highest severity test (K3) exhibited the highest value of DFS. X ray photoelectron spectroscopy (XPS) provided elemental composition, core level binding energies and the speciation of C, N, O, Si and S. As a result, L2 debris was found to originate from two processes: fracture of rubber and segregation of extender oil. Evidence has come both from morphology and XPS. Particles of H2 and K3 were ascribed to fracture alone. Comparison between K3 and the reference material, rasped rubber (RAS), shows the following: a) increase of the [S]/[C] surface atomic concentration ratio from RAS to K3; b) existence of multiple bonding states of S in K3 with energy peaking at 162.9 ± 0.3 eV ([-S-S-]n); c) weak contribution of R-S-O-R oxidized S species in K3 at 165 eV, not seen in RAS; d) no evidence of either SO3 or SO4 groups in any material. Although preliminary, these results prove the ability of morphological analysis and XPS to characterize the surface properties of debris particles non destructively.

scholarly journals Synthesis of Three-Dimensional Fe3O4/Graphene Aerogels for the Removal of Arsenic Ions from Water

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Yan Ye ◽  
Da Yin ◽  
Bin Wang ◽  
Qingwen Zhang
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
3D Structure ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Graphene Aerogels ◽  
Transmission Electron ◽  
Potential Applications ◽  
Removal Of Arsenic

We report the synthesis of three-dimensional Fe3O4/graphene aerogels (GAs) and their application for the removal of arsenic (As) ions from water. The morphology and properties of Fe3O4/GAs have been characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and superconducting quantum inference device. The 3D nanostructure shows that iron oxide nanoparticles are decorated on graphene with an interconnected network structure. It is found that Fe3O4/GAs own a capacity of As(V) ions adsorption up to 40.048 mg/g due to their remarkable 3D structure and existence of magnetic Fe3O4nanoparticles for separation. The adsorption isotherm matches well with the Langmuir model and kinetic analysis suggests that the adsorption process is pseudo-second-ordered. In addition to the excellent adsorption capability, Fe3O4/GAs can be easily and effectively separated from water, indicating potential applications in water treatment.

Electronic structure modification in Fe substituted β-Ga2O3 from resonant photoemission and soft x-ray absotption spectroscopies

2021 ◽  
Author(s):  
Sahadeb Ghosh ◽  
Mangala Nand ◽  
Rajiv Kamparath ◽  
Mukul Gupta ◽  
Devdatta M Phase ◽  
...  
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Rf Magnetron Sputtering ◽  
Binding Energies ◽  
Transfer System ◽  
Structure Modification ◽  
X Ray ◽  
Resonant Photoemission ◽  
A Charge ◽  
Fe Substitution

Abstract Oriented thin films of β-(Ga1-xFex)2O3 have been deposited by RF magnetron sputtering on c-Al2O3 and GaN substrates. The itinerant character of Fe 3d states forming the top of the valence band (VB) of Fe substituted of β-Ga2O3 thin films has been determined from resonant photoelectron spectroscopy (RPES). Further, admixture of itinerant and localized character of these Fe 3d sates is obtained for larger binding energies i.e deeper of VB. The bottom of the conduction band (CB) for β-(Ga1-xFex)2O3 is also found to be strongly hybridized states involving Fe 3d and O 2p states as compared to that of Ga 4s in pristine β-Ga2O3. This suggests that β-Ga2O3 transforms from band like system to a charge transfer system with Fe substitution. Furthermore, the bandgap red shits with Fe composition, which has been found to be primarily related to the shift of the CB edge.

scholarly journals Synthesis of new Ln4(Al2O6F2)O2 (Ln = Sm, Eu, Gd) phases with a cuspidine-related structure

IUCrJ ◽  
2019 ◽  
Vol 6 (1) ◽  
pp. 128-135 ◽  
Author(s):  
Aroa Morán-Ruiz ◽  
Aritza Wain-Martin ◽  
Alodia Orera ◽  
María Luisa Sanjuán ◽  
Aitor Larrañaga ◽  
...  
Keyword(s):  
Rare Earth ◽  
Low Temperature ◽  
Raman Spectra ◽  
Photoelectron Spectroscopy ◽  
Binding Energies ◽  
Temperature Reaction ◽  
Rietveld Refinements ◽  
X Ray ◽  
Vinylidene Difluoride ◽  
Vacant Position

The first fluorination of the cuspidine-related phases of Ln4(Al2O7□)O2 (where Ln = Sm, Eu, Gd) is reported. A low-temperature reaction with poly(vinylidene difluoride) lead to the fluorine being substituted in place of oxygen and inserted into the vacant position between the dialuminate groups. X-ray photoelectron spectroscopy shows the presence of the F 1s photoelectron together with an increase in Al 2p and rare-earth 4d binding energies supporting F incorporation. Energy-dispersive X-ray spectroscopy analyses are consistent with the formula Ln4(Al2O6F2)O2, confirming that substitution of one oxygen by two fluoride atoms has been achieved. Rietveld refinements show an expansion in the cell upon fluorination and confirm that the incorporation of fluoride in the Ln4(Al2O7□)O2 structure results in changes in Al coordination from four to five. Thus, the isolated tetrahedral dialuminate Al2O7 groups are converted to chains of distorted square-based pyramids. These structural results are also discussed based on Raman spectra.

scholarly journals On the prediction of core level binding energies in molecules, surfaces and solids

2018 ◽  
Vol 20 (13) ◽  
pp. 8403-8410 ◽  
Author(s):  
Francesc Viñes ◽  
Carmen Sousa ◽  
Francesc Illas
Keyword(s):  
Photoelectron Spectroscopy ◽  
State Of The Art ◽  
Binding Energies ◽  
Core Level ◽  
Chemical Environment ◽  
X Ray ◽  
Unique Information

Core level binding energies, measured by X-ray photoelectron spectroscopy providing unique information regarding the chemical environment of atoms in a system, can be estimated by a diversity of state-of-the-art accurate methods here detailed.

Determination of the oxidation state of manganese in lepidolite by X-ray photoelectron spectroscopy

Clay Minerals ◽  
1982 ◽  
Vol 17 (4) ◽  
pp. 477-481 ◽  
Author(s):  
S. Evans ◽  
E. Raftery
Keyword(s):  
Oxidation State ◽  
Photoelectron Spectroscopy ◽  
Electronic Spectroscopy ◽  
Binding Energies ◽  
Core Electron ◽  
X Ray ◽  
Occasional Occurrence ◽  
The Subject ◽  
Electron Binding Energies

It is usually assumed that the oxidation state of the small proportion of Mn sometimes present in micas is +2, although there is evidence from electronic spectroscopy (Burns, 1970) for at least the occasional occurrence of Mn(III) in manganophyllite. We describe here X-ray photoelectron spectroscopic (XPS) measurements on the Mn in a Norwegian lepidolite which was the subject of a concurrent structural study by X-ray photoelectron diffraction (Evans & Raftery, 1982). To establish the Mn oxidation state we have compared the Mn2p core-electron binding energies (BE), the Mn2P3/2-O ls BE differences, and the Mn2p XPS peak profiles from the four common oxides of manganese (MnO, Mn3O4, Mn2O3 and MnO2) with those from the lepidolite. A re-examination of these oxides was undertaken because the agreement between reports in the literature was unsatisfactory, and uncertainty existed concerning the integrity of some of the surfaces previously examined.

X-Ray photoelectron spectroscopy of monosubstituted perfluorobenzenes

1977 ◽  
Vol 55 (8) ◽  
pp. 1279-1284 ◽  
Author(s):  
Barry C. Trudell ◽  
S. James W. Price
Keyword(s):  
Gas Phase ◽  
Photoelectron Spectroscopy ◽  
Binding Energies ◽  
Photoelectron Spectra ◽  
Atomic Charges ◽  
X Ray ◽  
Sophisticated Analysis ◽  
Charge Calculations

The gas phase X-ray photoelectron spectra, XPS, were observed for the series C6F5X (X = F, Cl, I, Br, H). Binding energies were determined from the spectra using the ESCAPLOT Program. Charge calculations were carried out using Equalization of Electronegativity, CNDO/2, and ACHARGE approaches on each molecule. The more sophisticated analysis leads to the following equation correlating the (C 1s) binding energies and the atomic charges qi[Formula: see text]

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