The Soft X-Ray Valence Band Spectra and the Heat of Formation of Chemical Compounds and Alloys

ABSTRACTX-ray photoelectron spectroscopy of pure and K chemisorbed VxOy/TiO2 powders are reported. Core-line and valence band spectra suggest the presence of vanadium open shell ions on the pure VxOy/TiO2 interface, whereas potassium vanadate seems to form after K chemisorption. That results in the presence of a significant amount of gap states, with vanadium character, just above the O2p band edge, for the pure VxOy/TiO2 powder, while K chemisorption, reducing significantly the open shell vanadium ions, quenches the gap emission in the XPS valence band spectra.

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The Surface Analysis of Nickel Chromia Catalysts by X-Ray Photoelectron Spectroscopy

Canadian Journal of Chemistry ◽

10.1139/v73-250 ◽

1973 ◽

Vol 51 (10) ◽

pp. 1670-1672 ◽

Cited By ~ 6

Author(s):

Norman Stewart McIntyre ◽

Norman Henry Sagert ◽

Rita Mary Louise Pouteau ◽

Warren George Proctor

Keyword(s):

Valence Band ◽

Surface Analysis ◽

Photoelectron Spectroscopy ◽

Isotope Exchange ◽

Surface Composition ◽

X Ray ◽

Hydrogen Water ◽

Band Spectra ◽

Composition Changes

The surface composition of a series of nickel–chromia catalysts has been examined by X-ray photoelectron spectroscopy. Correlation of the amount of available surface nickel with the activity of the particular catalyst for hydrogen water deuterium isotope exchange is very good. No significant alterations are observed in the valence band spectra as the surface composition changes.

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Phase identification in binary mixture of nanopowders from deconvoluted valence band spectra using X-ray photoelectron spectroscopy: Case study with iron oxide and titania polymorphs

Applied Surface Science ◽

10.1016/j.apsusc.2018.08.132 ◽

2018 ◽

Vol 462 ◽

pp. 932-943 ◽

Cited By ~ 3

Author(s):

D. Nanda Gopala Krishna ◽

C. Anushree ◽

R.P. George ◽

John Philip

Keyword(s):

Iron Oxide ◽

Binary Mixture ◽

Valence Band ◽

Photoelectron Spectroscopy ◽

Phase Identification ◽

X Ray ◽

Band Spectra

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Characterization of Fluorinated Multi-Walled and Single-Walled Carbon Nanotubes Using High Resolution XPS and EDX

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.699.194 ◽

2013 ◽

Vol 699 ◽

pp. 194-199

Author(s):

Ling Zhi Sun ◽

Xu Zhang

Keyword(s):

Carbon Nanotubes ◽

High Resolution ◽

Binding Energy ◽

Valence Band ◽

Single Walled Carbon Nanotubes ◽

X Ray ◽

Single Walled Carbon ◽

Multi Walled Carbon Nanotubes ◽

Band Spectra ◽

Walled Carbon Nanotubes

Pristine and fluorinated multi-walled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs) were characterized using energy dispersive X-ray spectra (EDX) and X-ray photoelectron spectroscopy (XPS), respectively. The fluorine percentages of fluorinated multi-walled carbon nanotubes (F-MWCNTs) and fluorinated single-walled carbon nanotubes (F-SWCNTs) were 10.42% and 9.67% respectively by EDX. The absorption and de-absorption of fluorine properties were studied using high resolution C 1s and F 1s core level XPS and valence band spectra. The fluorine can be completely dissociated from F-MWCNTs, but partially dissociated from SWCNTs. There was 5.79% fluorine in atomic percent remaining associated with the F-SWCNTs when annealing the nanotubes to 500 °C measured by EDX. The results of F 1s core level XPS indicated that the binding energy of fluorine associated on SWCNTs was shifted from 687.0 eV to 688.3 eV after annealing the nanotubes to 500 °C. The results of valence band spectra showed that the binding energy of F 2p and F 2s shifted from 7.5 eV and 31.0 eV to 8.8 eV and 32.5 eV respectively in SWCNTS. However, the two peaks disappeared in annealed MWCNTs.

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An ionicity scale based on x‐ray photoemission valence‐band spectra of ANB8−Nand ANB10−Ntype crystals

The Journal of Chemical Physics ◽

10.1063/1.1682422 ◽

1974 ◽

Vol 61 (7) ◽

pp. 2850-2856 ◽

Cited By ~ 50

Author(s):

S. P. Kowalczyk ◽

L. Ley ◽

F. R. McFeely ◽

D. A. Shirley

Keyword(s):

Valence Band ◽

X Ray ◽

Band Spectra

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HIGH SPATIAL RESOLUTION SOFT X-RAY PHOTOEMISSION STUDY OF WO3 THIN FILMS

Surface Review and Letters ◽

10.1142/s0218625x02002518 ◽

2002 ◽

Vol 09 (01) ◽

pp. 375-380 ◽

Cited By ~ 3

Author(s):

L. LOZZI ◽

M. PASSACANTANDO ◽

S. SANTUCCI ◽

S. LA ROSA ◽

N. YU. SVETCHNIKOV

Keyword(s):

Valence Band ◽

Film Surface ◽

Photoemission Spectroscopy ◽

X Ray ◽

Thin Film Surface ◽

High Lateral Resolution ◽

Band Spectra ◽

Photoemission Study ◽

First Time ◽

Wo3 Thin Films

WO 3 thin film surface chemical composition has been studied by means of high resolution soft X-ray photoemission spectroscopy. Valence band and W 4f core levels have been analyzed on different sample positions and high lateral resolution images have been acquired. The valence band spectra have shown for the first time a marked increase of the W 5d density of state at the Fermi level, indicating the presence of metallic tungsten on the surface. This has been confirmed by the W 4f signal, which presents both metallic and oxidized phases. For the first time, spectromicroscopy on core states has clearly evidenced the presence of nonstoichiometric areas and a spatial localization of W 4+ states on the surface.

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