Chemical degradation of selected Zn-based corrosion products induced by C60 cluster, Ar cluster and Ar+ ion sputtering in the focus of X-ray photoelectron spectroscopy (XPS)

2017 ◽  
Vol 403 ◽  
pp. 15-22 ◽  
Author(s):  
R. Steinberger ◽  
J. Sicking ◽  
J. Weise ◽  
J. Duchoslav ◽  
T. Greunz ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Corrosion Products ◽  
Chemical Degradation ◽  
Ion Sputtering ◽  
X Ray

Anelastic Phenomena at the Fibre-Matrix Interface of the Ti6Al4V-SiCf Composite

2010 ◽  
Vol 425 ◽  
pp. 263-270 ◽  
Author(s):  
Paolo Deodati ◽  
Riccardo Donnini ◽  
Saulius Kaciulis ◽  
Alessio Mezzi ◽  
Roberto Montanari ◽  
...  
Keyword(s):  
Activation Energy ◽  
Relaxation Time ◽  
Photoelectron Spectroscopy ◽  
Chemical Characterization ◽  
Matrix Interface ◽  
Ion Sputtering ◽  
Mechanical Spectroscopy ◽  
Monolithic Alloy ◽  
X Ray ◽  
Fibre Matrix

The composite, consisting of Ti6Al4V matrix reinforced by unidirectional SiC fibres (SCS-6), has been investigated by mechanical spectroscopy at temperatures up to 1,173 K. For comparison, the same experiments have been performed on the corresponding monolithic alloy. The internal friction (IF) spectrum of the composite exhibits a new relaxation peak superimposed to an exponentially increasing background. This peak, which is not present in the monolithic alloy, has an activation energy H = 186 kJ mol-1 and a relaxation time 0 = 2.3 x 10-15 s. The phenomenon has been attributed to a reorientation of interstitial-substitutional pairs in the  phase of Ti6Al4V matrix around the fibres. This explanation is supported by the results of micro-chemical characterization carried out by X-ray photoelectron spectroscopy (XPS) combined with Ar ion sputtering.

scholarly journals Fabrication of ZnO nanocatalyst as an excellent heterogeneous catalyst applicant for Methyl Orange dye degradation in aqueous medium.

2021 ◽  
Author(s):  
Zaheer Ahmed Mahar ◽  
Ghulam Qadir Shar ◽  
Aamna Balouch
Keyword(s):  
Methyl Orange ◽  
Aqueous Medium ◽  
Photoelectron Spectroscopy ◽  
Dye Degradation ◽  
Catalytic Efficiency ◽  
Chemical Degradation ◽  
X Ray ◽  
Nano Catalyst ◽  
Methyl Orange Dye ◽  
Short Time

Abstract The current paper describes the fabrication of an excellent and economical heterogeneous nanocatalyst for the degradation of methyl orange dye in aqueous medium. ZnO/PVP nanocatalyst has been successfully synthesized by the chemical degradation route, followed by ultrasonication. The size, shape and crystalline structure of synthesized ZnO/PVP nano composite was characterized by UV-visible spectroscopy, X-ray diffractometry, Dynamic Scattering Light, Zeta Potential, Fourier transform infrared spectroscopy, Scanning Electron Microscope, Energy Dispersive X-ray and X-ray photoelectron spectroscopy. To authenticate the catalytic efficiency of nanocatalyst, the fabricated ZnO/PVP nanocompoiste was screened for methyl orange dye degradation. Finally, synthesized nanocatalyst exhibited an admirable catalytic efficiency, above 98% of methyl orange degradation observed just in 90 seconds using least catalyst dose (150μg) in aqueous medium. The engineered ZnO/PVA nanocomposite shows several advantages over traditional methods for the degradation of hazard and toxic dyes, such as high percentage degradation, short time and minimum dose of nano catalyst and excellent reusability. It is suggested that this rare nanocatalyst may be used successfully on commercial level for degradation toxic pollutants.

scholarly journals Chemical Degradation of the La0.6Sr0.4Co0.2Fe0.8O3−δ/Ce0.8Sm0.2O2−δ Interface during Sintering and Cell Operation

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3674
Author(s):  
Mélanie François ◽  
Maria Paola Carpanese ◽  
Olivier Heintz ◽  
Victoire Lescure ◽  
Davide Clematis ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Perovskite Phase ◽  
Tape Casting ◽  
Chemical Degradation ◽  
Doped Ceria ◽  
Sintering Process ◽  
X Ray ◽  
Cell Testing ◽  
Complete Cell ◽  
Degradation Of Materials

A complete cell consisting of NiO-Ce0.8Sm0.2O3−δ//Ce0.8Sm0.2O3−δ//(La0.6Sr0.4)0.95Co0.2Fe0.8O3−δ elaborated by a co-tape casting and co-sintering process and tested in operating fuel cell conditions exhibited a strong degradation in performance over time. Study of the cathode–electrolyte interface after cell testing showed, on one hand, the diffusion of lanthanum from (La0.6Sr0.4)0.95Co0.2Fe0.8O3−δ into Sm-doped ceria leading to a La- and Sm-doped ceria phase. On the other hand, Ce and Sm diffused into the perovskite phase of the cathode. The grain boundaries appear to be the preferred pathways of the cation diffusion. Furthermore, a strontium enrichment was clearly observed both in the (La0.6Sr0.4)0.95Co0.2Fe0.8O3−δ layer and at the interface with electrolyte. X-ray photoelectron spectroscopy (XPS) indicates that this Sr-rich phase corresponded to SrCO3. These different phenomena led to a chemical degradation of materials and interfaces, explaining the decrease in electrochemical performance.

scholarly journals Effect of Si Content on the Corrosion Behavior of 420 MPa Weathering Steel

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 486 ◽  
Author(s):  
Sun ◽  
Yu ◽  
Zhang ◽  
Yan ◽  
Lu ◽  
...  
Keyword(s):  
Corrosion Rate ◽  
Corrosion Behavior ◽  
Photoelectron Spectroscopy ◽  
Silicon Oxide ◽  
Corrosion Products ◽  
Weathering Steel ◽  
X Ray ◽  
Initial Stage ◽  
Amorphous Compounds ◽  
Si Content

: The effect of Si content (0.12%, 0.34%, and 0.48%) on the corrosion behavior of weathering steel in a simulated marine environment was investigated in a dry/wet alternating cycle corrosion experiment. Corrosion weight gain, X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and electrochemical methods were used to measure the regularity and nature of the rust. The results show that the corrosion process could be divided into an initial stage where the corrosion rate increased and a later stage where the corrosion rate decreased before remaining stable. The corrosion rate was the lowest for a Si content in the weathering steel of 0.48%. The corrosion products of all three steel groups contains α-FeOOH, β-FeOOH, γ-FeOOH, Fe3O4, and large amounts of amorphous compounds. Furthermore, Si benefits the transformation of β-FeOOH and γ-FeOOH to stable phases. The addition of the Si alloying element is beneficial to the formation of dense and compact rust layers that enhance the electrochemical resistance of weathering steel and silicon oxide influences the self-corrosion potential of the corrosion products.

Some Boiler Tubes Crack Reason Analysis

2013 ◽  
Vol 405-408 ◽  
pp. 3253-3258 ◽  
Author(s):  
Ling Pan ◽  
Xue Jun Xie ◽  
Jun Shen ◽  
Zhao Li ◽  
Rui Wang ◽  
...  
Keyword(s):  
High Temperature ◽  
Power Plant ◽  
Photoelectron Spectroscopy ◽  
Element Composition ◽  
Corrosion Products ◽  
Back Side ◽  
X Ray ◽  
Boiler Tubes ◽  
Scanning Electron

Aiming at some boiler tubescrack in a power plant, the element composition and the valence of elements in corrosion products on the outer surfaces of the boiler tubes were analysed by Scanning Electron Microanalyzer (SEM) and X-ray Photoelectron Spectroscopy (XPS), and the corrosion reason and mechanism of the outer surfaces of the boiler tubes were studied.The results showed as follows. (1)The content of element S in the corrosion products on the outer surfaces of the fire side boiler tubes was bigger than that in the corrosion products on the outer surfaces of the back side boiler tubes and the corrosion of the outer surfaces of the fire side boiler tubes was more serious than that of the outer surfaces of the back side boiler tubes. (2) the element S in the corrosion products existed in the form of sulfate (SO42-), because the valence of S in the corrosion products on the outer surfaces of the fire side boiler tubes and the back side boiler tubes was +6, not-2. (3) the element Fe in the corrosion products on the outer surfaces of the fire side boiler tubes and the back side boiler tubes existed in the form of Fe3O4, Fe2O3 or Fe2(SO4)3. (4) The corrosion of the boiler tubes was induced by sulphate under high temperature, and aggravated with the temperature of the outer surfaces of the boiler tubes elevated.

X-ray photoelectron spectroscopy studies of silicon suboxides obtained by the sol-gel method

1997 ◽  
Vol 12 (1) ◽  
pp. 100-105 ◽  
Author(s):  
S. Santucci ◽  
E. Cordeschi ◽  
L. Lozzi ◽  
M. Passacantando ◽  
P. Picozzi ◽  
...  
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Sol Gel ◽  
Dip Coating ◽  
Silicon Substrates ◽  
Ion Sputtering ◽  
X Ray ◽  
Coating Methods ◽  
Spectroscopy Studies ◽  
Compositional Properties

Silicon suboxides thin films obtained by sol-gel and dip-coating methods, starting from a sol containing different percentages of TEOS (tetraethoxysilane) and MTEOS (methyltriethoxysilane), were grown onto silicon substrates. The samples were annealed at 100, 300, and 500 °C, and the electronic and compositional properties of the surface were studied by x-ray photoelectron spectroscopy (XPS) detecting the Si “Auger parameter” and the valence band. The effects produced by an ion-sputtering treatment of the samples were also studied.

Characterization of Tungsten Surfaces by Simultaneous Work Function and Secondary Electron Emission Measurements

2003 ◽  
Vol 9 (4) ◽  
pp. 337-342 ◽  
Author(s):  
Gy. Vida ◽  
V.K. Josepovits ◽  
M. Győr ◽  
P. Deák
Keyword(s):  
Work Function ◽  
Electron Emission ◽  
Photoelectron Spectroscopy ◽  
Secondary Electron ◽  
Direct Relationship ◽  
Secondary Electron Emission ◽  
Ion Sputtering ◽  
X Ray ◽  
Simultaneous Change

The changes of the work function (Φ) and the secondary electron emission (SEE) of oxygen covered polycrystalline tungsten occurring after ion sputtering and heat treatments have been investigated. The chemical composition was analyzed by X-ray photoelectron spectroscopy (XPS), and the electron emission properties by work function spectroscopy (WFS). We observed in what manner the chemical changes of the surface are reflected in the work function and SEE. The simultaneous change of Φ and SEE in the case of oxygen covered tungsten have been pointed out and a direct relationship between them can be supposed.

scholarly journals XPS and FT-IR Characterization of Selected Synthetic Corrosion Products of Zinc Expected in Neutral Environment Containing Chloride Ions

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Juliusz Winiarski ◽  
Włodzimierz Tylus ◽  
Katarzyna Winiarska ◽  
Irena Szczygieł ◽  
Bogdan Szczygieł
Keyword(s):  
Photoelectron Spectroscopy ◽  
Surface Composition ◽  
Chloride Ions ◽  
Corrosion Products ◽  
Zinc Alloy ◽  
Solid State Method ◽  
X Ray ◽  
Ft Ir ◽  
Atr Spectroscopy

ZnO, Zn(OH)2, Zn5(OH)8Cl2·H2O, ZnCO3, and Zn5(CO3)2(OH)6 synthetic powders were prepared by chemical or solid-state method. Their crystalline phase structure, thermal behavior, and morphology were examined. Characteristic infrared absorbance bands were estimated by means of FT-IR ATR spectroscopy. X-ray photoelectron spectroscopy (XPS) allowed to calculate the modified Auger parameters (α ′) thereof to 2010.2, 2009.3, 2009.4, 2009.7, and 2009.8 eV, respectively for ZnO, Zn(OH)2, Zn5(OH)8Cl2·H2O, ZnCO3, and Zn5(CO3)2(OH)6. Finally, comparison of surface composition may be crucial to evaluation of the unknown experimental spectra of corrosion products formed on the surface of zinc alloy coatings exposed in NaCl solution.

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