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

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.

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Physical genetics: Cross-breeding density functional theory and X-ray photoelectron spectroscopy to rationalize chemical shifts of binding energies in solid compounds

Solid State Sciences ◽

10.1016/j.solidstatesciences.2020.106359 ◽

2020 ◽

Vol 110 ◽

pp. 106359

Author(s):

Horst P. Beck ◽

Giuliano Moretti

Keyword(s):

Density Functional Theory ◽

Photoelectron Spectroscopy ◽

Density Functional ◽

Chemical Shifts ◽

Binding Energies ◽

Breeding Density ◽

Functional Theory ◽

X Ray ◽

Cross Breeding ◽

Solid Compounds

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Green Synthesis of Feather-Shaped MoS2/CdS Photocatalyst for Effective Hydrogen Production

International Journal of Photoenergy ◽

10.1155/2013/247516 ◽

2013 ◽

Vol 2013 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Yang Liu ◽

Hongtao Yu ◽

Xie Quan ◽

Shuo Chen

Keyword(s):

Electron Microscopy ◽

Hydrogen Production ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance ◽

Sulfur Source ◽

X Ray ◽

Transmission Electron ◽

Microscopy Images ◽

Effective Hydrogen ◽

Better Than

MoS2/CdS photocatalyst was fabricated by a hydrothermal method for H2production under visible light. This method used low toxic thiourea as a sulfur source and was carried out at 200°C. Thus, it was better than the traditional methods, which are based on an annealing process at relatively high temperature (above 400°C) using toxic H2S as reducing agent. Scanning electron microscopy and transmission electron microscopy images showed that the morphologies of MoS2/CdS samples were feather shaped and MoS2layer was on the surface of CdS. The X-ray photoelectron spectroscopy testified that the sample was composed of stoichiometric MoS2and CdS. The UV-vis diffuse reflectance spectra displayed that the loading of MoS2can enhance the optical absorption of MoS2/CdS. The photocatalytic activity of MoS2/CdS was evaluated by producing hydrogen. The hydrogen production rate on MoS2/CdS reached 192 μmol·h−1. This performance was stable during three repeated photocatalytic processes.

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

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/ac43dc ◽

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.

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

IUCrJ ◽

10.1107/s205225251801744x ◽

2019 ◽

Vol 6 (1) ◽

pp. 128-135 ◽

Cited By ~ 1

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.

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

Physical Chemistry Chemical Physics ◽

10.1039/c7cp08503f ◽

2018 ◽

Vol 20 (13) ◽

pp. 8403-8410 ◽

Cited By ~ 16

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.

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

Clay Minerals ◽

10.1180/claymin.1982.017.4.11 ◽

1982 ◽

Vol 17 (4) ◽

pp. 477-481 ◽

Cited By ~ 10

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.

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X-Ray photoelectron spectroscopy of monosubstituted perfluorobenzenes

Canadian Journal of Chemistry ◽

10.1139/v77-177 ◽

1977 ◽

Vol 55 (8) ◽

pp. 1279-1284 ◽

Cited By ~ 6

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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