Near-surface chemistry in Zr2Fe and ZrVFe studied by means of x-ray photoemission spectroscopy: A temperature-dependent study

2000 ◽  
Vol 18 (6) ◽  
pp. 2950-2956 ◽  
Author(s):  
Janez Kovac ◽  
Oumar Sakho ◽  
Paolo Manini ◽  
M. Sancrotti
Keyword(s):  
Surface Chemistry ◽  
Photoemission Spectroscopy ◽  
Temperature Dependent ◽  
Near Surface ◽  
X Ray ◽  
Temperature Dependent Study

A Surface Analytical Study of the Effects of Water and Oxygen on Tribological Behavior of DLC Films

2005 ◽  
Author(s):  
O. L. Eryilmaz ◽  
A. Erdemir ◽  
J. A. Johnson ◽  
N. Mehta ◽  
B. Prorok
Keyword(s):  
Surface Chemistry ◽  
Friction And Wear ◽  
Analytical Study ◽  
Tribological Behavior ◽  
Mechanistic Explanation ◽  
Sliding Contact ◽  
Diamond Like Carbon ◽  
Near Surface ◽  
X Ray ◽  
Contact Surfaces

In this study, we explored the effects of water and oxygen molecules on friction and wear of diamond-like carbon (DLC) films. Specifically, using Raman and x-ray photoelectron spectroscopies we attempted to analyze the near surface chemistry and microstructure of sliding contact surfaces and correlated these findings with changes in friction and wear of DLC films. Tribological tests were run in a ball-on-disk machine under 2 to 5 N loads and in dry and moist nitrogen and oxygen environments. Based on the tribological and surface analytical findings, a mechanistic explanation is provided for the high friction and wear of DLC in dry and humid oxygen environments.

scholarly journals The Debye Temperature for Hydrothermally Grown ThO2 Single Crystals

2013 ◽  
Vol 1576 ◽  
Author(s):  
Tony D. Kelly ◽  
James C. Petrosky ◽  
John W. McClory ◽  
Timothy Zens ◽  
David Turner ◽  
...  
Keyword(s):  
Electronic Properties ◽  
Single Crystals ◽  
Debye Temperature ◽  
Oxidation State ◽  
Core Level ◽  
Photoemission Spectroscopy ◽  
Temperature Dependent ◽  
X Ray ◽  
Temperature Range

ABSTRACTThe electronic properties of ThO2 single crystals were studied using x-ray photoemission spectroscopy (XPS). The XPS results show that the Th 4f core level is in an oxidation state that is consistent with that expected for Th in ThO2. The effective Debye temperature is estimated from the temperature dependent photoemission intensities of the Th 4f core level over the temperature range of 290 to 360 K. A Debye temperature of 468±32 K has been determined.

Surface and dynamical properties of GeI2

2D Materials ◽  
2021 ◽  
Author(s):  
Archit Dhingra ◽  
Alexey Lipatov ◽  
Haidong Lu ◽  
Katerina Chagoya ◽  
Joseph Dalton ◽  
...  
Keyword(s):  
Band Gap ◽  
Debye Temperature ◽  
Wide Band ◽  
Core Level ◽  
Photoemission Spectroscopy ◽  
Bulk Temperature ◽  
Level Shift ◽  
Temperature Dependent ◽  
X Ray ◽  
Optical Absorbance

Abstract GeI2 is an interesting two-dimensional (2D) wide-band gap semiconductor because of diminished edge scattering due to an absence of dangling bonds. Angle-resolved x-ray photoemission spectroscopy (ARXPS) indicates a germanium rich surface, and a surface to bulk core-level shift of 1.8 eV in binding energy, between the surface and bulk components of the Ge 2p3/2 core-level, making clear that the surface is different from the bulk. Temperature dependent studies indicate an effective Debye temperature (θD ) of 186 ± 18 K for the germanium x-ray photoemission spectroscopy (XPS) feature associated with the surface. These measurements also suggest an unusually high effective Debye temperature for iodine (587 ± 31 K), implying that iodine is present in the bulk of the material, and not the surface. From optical absorbance, GeI2 is seen to have an indirect (direct) optical band gap of 2.60 (2.8) ± 0.02 (0.1) eV, consistent with the expectations. Temperature dependent magnetometry indicates that GeI2 is moment paramagnetic at low temperatures (close to 4 K) and shows a diminishing saturation moment at high temperatures (close to 300 K and above).

ESCA and solid-state NMR studies of allophane

Clay Minerals ◽  
1995 ◽  
Vol 30 (3) ◽  
pp. 201-209 ◽  
Author(s):  
N. He ◽  
T. L. Barr ◽  
J. Klinowski
Keyword(s):  
Solid State ◽  
Surface Chemistry ◽  
Photoelectron Spectroscopy ◽  
Solid State Nmr ◽  
Bulk Material ◽  
Binding Energies ◽  
Nmr Studies ◽  
Near Surface ◽  
X Ray ◽  
The Core

AbstractThe surface/near-surface chemistry of allophane has been studied by X-ray photoelectron spectroscopy (ESCA) and the bulk material by 27A1 and 29Si solid-state NMR and other techniques. The surface/near-surface Si/Al ratio of allophane is c.1.0, similar to that for kaolinite, zeolite Na-A and sodalite. The core level binding energies for kaolinite and allophane are almost identical, but quite different from those for zeolite Na-A and sodalite, both framework aluminosilicates. The nature and size of these differences is consistent with the differences between the chemistry of sheet and framework silicates. The small variations in the Si(2p) spectra for kaolinite and allophane are discussed in terms of bonding of the tetrahedral units in the two materials.

X-ray magnetic circular dichroism temperature dependent study of RCo2 compounds

2000 ◽  
Vol 87 (9) ◽  
pp. 5881-5883 ◽  
Author(s):  
F. Garcia ◽  
L. C. Sampaio ◽  
A. Y. Takeuchi ◽  
H. Tolentino ◽  
A. Fontaine
Keyword(s):  
Circular Dichroism ◽  
Magnetic Circular Dichroism ◽  
Temperature Dependent ◽  
X Ray ◽  
Circular Dichroïsm ◽  
Temperature Dependent Study

scholarly journals An investigation into the surface termination and near-surface bulk doping of oxygen-terminated diamond with lithium at various annealing temperatures

MRS Advances ◽  
2021 ◽  
Author(s):  
Sami Ullah ◽  
Liam Cullingford ◽  
Tongfei Zhang ◽  
Jing Ren Wong ◽  
Gary Wan ◽  
...  
Keyword(s):  
Surface Functionalization ◽  
Annealing Temperature ◽  
Photoemission Spectroscopy ◽  
Chemical Route ◽  
Near Surface ◽  
X Ray ◽  
Surface Termination ◽  
Annealing Temperatures ◽  
Alternative Method ◽  
Stoichiometric Ratios

Abstract An alternative method of doping and surface functionalization of diamond using a chemical route was explored. The interaction of Li with the surface and bulk of oxygen-terminated diamond was investigated using Angle-Resolved X-ray Photoemission Spectroscopy (ARXPS). A stable LiO2 termination of diamond (100) surface and doping of near-surface diamond bulk was achieved up to an annealing temperature of 850 °C. The changes in interaction between the species involved (C, O, Li) and their stoichiometric ratios at the surface were investigated as a function of annealing temperature. This was done using ARXPS peak analysis. Graphic abstract

Sign in / Sign up

Export Citation Format

Share Document