An X-Ray Photoelectron Study of Doped and Supported Nickel Oxide

1985 ◽  
Vol 38 (9) ◽  
pp. 1293 ◽  
Author(s):  
SJ Cochran ◽  
FP Larkins
Keyword(s):  
Activation Energy ◽  
Electron Transport ◽  
Nickel Oxide ◽  
Photoelectron Spectroscopy ◽  
Oxide Surface ◽  
X Ray ◽  
Peak Intensity ◽  
Photoelectron Study ◽  
Supported Oxides ◽  
Doped Oxide

The surfaces of lithium-and chromium-doped nickel oxide and of nickel oxide supported on alumina have been examined by X-ray photoelectron spectroscopy. The concentration of the nickel(III) species increased for the lithium-doped oxide and decreased for the chromium-doped oxide relative to the undoped oxide. The effects of doping were manifested most clearly however by the amount of oxygen-containing species adsorbed on the oxide surface rather than by variations in the nickel(III) peak intensity. Lithium-doped oxides were also shown to reduce more readily than undoped or chromium-doped oxides in the presence of carbon-containing impurities. The rate of reduction is influenced by the activation energy for electron transport which is related to the availability of the nickel(III) species. Supported oxides showed significant surface enhancement of nickel(II) as well as an absence of the nickel(III) species. The nickel(II) species in the supported oxide was not easily reduced to nickel(0).

scholarly journals Phytosynthetic Fabrication of Lanthanum Ion-Doped Nickel Oxide Nanoparticles Using Sesbania grandiflora Leaf Extract and Their Anti-Microbial Properties

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 124
Author(s):  
Srihasam Saiganesh ◽  
Thyagarajan Krishnan ◽  
Golla Narasimha ◽  
Hesham S. Almoallim ◽  
Sulaiman Ali Alhari ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Optical Properties ◽  
Rare Earth ◽  
Nickel Oxide ◽  
Photoelectron Spectroscopy ◽  
Metal Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Nio Nanoparticles ◽  
X Ray ◽  
Sesbania Grandiflora

Over the past few years, the photogenic fabrication of metal oxide nanoparticles has attracted considerable attention, owing to the simple, eco-friendly, and non-toxic procedure. Herein, we fabricated NiO nanoparticles and altered their optical properties by doping with a rare earth element (lanthanum) using Sesbania grandiflora broth for antibacterial applications. The doping of lanthanum with NiO was systematically studied. The optical properties of the prepared nanomaterials were investigated through UV-Vis diffuse reflectance spectra (UV-DRS) analysis, and their structures were studied using X-ray diffraction analysis. The morphological features of the prepared nanomaterials were examined by scanning electron microscopy and transmission electron microscopy, their elemental structure was analyzed by energy-dispersive X-ray spectral analysis, and their oxidation states were analyzed by X-ray photoelectron spectroscopy. Furthermore, the antibacterial action of NiO and La-doped NiO nanoparticles was studied by the zone of inhibition method for Gram-negative and Gram-positive bacterial strains such as Escherichia coli and Bacillus sublitis. It was evident from the obtained results that the optimized compound NiOLa-04 performed better than the other prepared compounds. To the best of our knowledge, this is the first report on the phytosynthetic fabrication of rare-earth ion Lanthanum (La3+)-doped Nickel Oxide (NiO) nanoparticles and their anti-microbial studies.

X-ray photoelectron spectroscopy study of the interaction of methanol with polycrystalline copper oxide surface

1996 ◽  
Vol 11 (7) ◽  
pp. 1605-1608 ◽  
Author(s):  
S. Badrinarayanan ◽  
A. B. Mandale ◽  
S. R. Sainkar
Keyword(s):  
Copper Oxide ◽  
Photoelectron Spectroscopy ◽  
Low Dose ◽  
Dissociative Adsorption ◽  
Methanol Decomposition ◽  
Oxide Surface ◽  
Polycrystalline Copper ◽  
Spectroscopy Study ◽  
Methanol Vapor ◽  
X Ray

Methanol decomposition on a clean polycrystalline copper oxide surface was studied by x-ray photoelectron spectroscopy (XPS). Methanol was adsorbed at 133 K and desorbed over a broad temperature range. When CuO was exposed to a very low dose of methanol vapor, dissociative adsorption takes place, leading to the formation of CH3O and H2O. This is attributed to the presence of preadsorbed oxygen on the CuO surface.

Oxidation Behavior of Cu60Zr30Ti10 Bulk Metallic Glass

2005 ◽  
Vol 20 (6) ◽  
pp. 1396-1403 ◽  
Author(s):  
C.Y. Tam ◽  
C.H. Shek
Keyword(s):  
Metallic Glass ◽  
Oxide Layer ◽  
Bulk Metallic Glass ◽  
Photoelectron Spectroscopy ◽  
Oxidation Kinetics ◽  
Oxide Surface ◽  
X Ray ◽  
Rate Law ◽  
Cu Content ◽  
Surface Morphologies

The oxidation kinetics of Cu60Zr30Ti10 bulk metallic glass and its crystalline counterpart were studied in oxygen environment over the temperature range of 573–773 K. The oxidation kinetics, measured with thermogravimetric analysis, of the metallic glass follows a linear rate law between 573 and 653 K and a parabolic rate law between 673 and 733 K. It was also found that the oxidation activation energy of metallic glass is lower than that of its crystalline counterpart. The x-ray diffraction pattern showed that the oxide layer is composed of Cu2O, CuO, ZrO2, and metallic Cu. Cu enrichment on the topmost oxide layer of the metallic glass oxidized at 573 K was revealed by x-ray photoelectron spectroscopy while there was a decrease in Cu content in the innermost oxide layer. The oxide surface morphologies observed from scanning electron microscopy showed that ZrO2 granules formed at low temperatures while whiskerlike copper oxides formed at higher temperatures.

scholarly journals Electrochemiluminescence Sensor Based on Electrospun Three-Dimensional Carbon Nanofibers for the Detection of Difenidol Hydrochloride

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3315 ◽  
Author(s):  
Hao Cheng ◽  
Zhengyuan Zhou ◽  
Yanqing Li ◽  
Wenyi Huang ◽  
Jun Feng ◽  
...  
Keyword(s):  
Carbon Nanofibers ◽  
Photoelectron Spectroscopy ◽  
Hydrofluoric Acid ◽  
Three Dimensional ◽  
Modified Electrodes ◽  
Good Recovery ◽  
X Ray ◽  
Peak Intensity ◽  
Poisoning In Children ◽  
Application Prospects

The detection of difenidol hydrochloride, which is a drug that is widely used for treating the nausea and vomiting symptoms caused by certain diseases, has been increasingly involved in cases of suicide via overdosing and of drug poisoning in children. A novel electrochemiluminescence (ECL) sensor for the simple and effective detection of difenidol hydrochloride was fabricated by modifying a glassy carbon electrode with three-dimensional carbon nanofibers (3D-CNFs). The 3D-CNFs were synthesized by electrospinning a mixture of montmorillonite (MMT) and polyacrylonitrile, carbonizing the electrospun product, and etching it with hydrofluoric acid. The form and structure of the 3D-CNFs was analyzed via scanning electron microscopy, X-ray photoelectron spectroscopy, and Raman microspectroscopy. According to the experimental results obtained using the modified electrodes, a good linear relationship was found between peak intensity and difenidol concentration (y = 868.14x − 61.04, R2 = 0.999), with a relatively low detection limit (8.64 × 10−10 mol·L−1 (S/N = 3)). In addition, our approach exhibited good recovery values ranging from 98.99% to 102.28%. The proposed novel ECL sensor has wide application prospects for the detection of difenidol hydrochloride.

scholarly journals Surface Stoichiometry and Optical Properties of Cux–TiyCz Thin Films Deposited by Magnetron Sputtering

Coatings ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 551 ◽  
Author(s):  
Avishek Roy ◽  
Arun Kumar Mukhopadhyay ◽  
Sadhan Chandra Das ◽  
Gourab Bhattacharjee ◽  
Abhijit Majumdar ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Magnetron Sputtering ◽  
Photoelectron Spectroscopy ◽  
Metal Matrix ◽  
Optical Band Gap ◽  
Matrix Composites ◽  
X Ray ◽  
Peak Intensity ◽  
Ternary Carbide

Ternary carbide in metal matrix composites constitute a big challenge in the industry, and in this regard their surface treatment is one of the most important issues. Ternary carbide (CuxTiyCz, where x, y and z are integers) thin films are synthesized by magnetron sputtering and characterized with respect to the film depth. X-ray photoelectron spectroscopy (XPS) of Cu-2p and Ti-2p peaks shows the associated shake-up satellite peaks at a smaller film depth; the peak intensity is reduced at a higher depth. The relative intensity of Cu and Ti increases at a larger film depth. The optical band gap varies from 1.83 to 2.20 eV at different film depths.

Grain Boundary Diffusion in Co/Cu and Co/Cr Magnetic Thin Films

1993 ◽  
Vol 313 ◽  
Author(s):  
John G. Holl-Pellerin ◽  
S.G.H. Anderson ◽  
P.S. Ho ◽  
K.R. Coffey ◽  
J.K. Howard ◽  
...  
Keyword(s):  
Thin Films ◽  
Activation Energy ◽  
Diffusion Coefficient ◽  
Grain Boundary ◽  
Photoelectron Spectroscopy ◽  
Boundary Diffusion ◽  
Magnetic Thin Films ◽  
Grain Boundary Diffusion ◽  
X Ray ◽  
Before And After

ABSTRACTX-ray photoelectron spectroscopy (XPS) has been used to investigate grain boundary diffusion of Cu and Cr through 1000 Å thick Co films in the temperature range of 325°C to 400°C. Grain boundary diffusivities were determined by modeling the accumulation of Cu or Cr on Co surfaces as a function of time at fixed annealing temperature. The grain boundary diffusivity of Cu through Co is characterized by a diffusion coefficient, D0gb, of 2 × 104 cm2/sec and an activation energy, Ea,gb, of 2.4 eV. Similarly, Cr grain boundary diffusion through Co thin films occurs with a diffusion coefficient, Do,gb, of 6 × 10-2cm2/sec and an activation energy, Ea,gb of 1.8 eV. The Co film microstructure has been investigated before and after annealing by x-ray diffraction and transmission electron Microscopy. Extensive grain growth and texturing of the film occurred during annealing for Co deposited on a Cu underlayer. In contrast, the microstructure of Co deposited on a Cr underlayer remained relatively unchanged upon annealing. Magnetometer Measurements have shown that increased in-plane coercivity Hc, reduced remanence squareness S, and reduced coercive squareness S* result from grain boundary diffusion of Cu and Cr into the Co films.

Nitridation by NO Or N2O of Si-SiO2 Interfaces

1999 ◽  
Vol 567 ◽  
Author(s):  
A. P. Caricato ◽  
F. Cazzaniga ◽  
G. F. Cerofolini ◽  
B. Crivelli ◽  
M. L. Polignano ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Chemical Nature ◽  
Surface Recombination ◽  
Surface Recombination Velocity ◽  
Oxide Surface ◽  
Complementary Information ◽  
X Ray ◽  
Recombination Velocity ◽  
Foreign Species

ABSTRACTX-ray photoelectron spectroscopy (XPS) and photocurrent measurements for the determination of surface recombination velocity provide complementary information on the structure of the Si-SiO2 interface, being sensitive to the chemical nature of foreign species at the interface the former, and to intrinsic defects the latter. The comparison of the XPS N(1s) peaks determined for the Si-Si0 2 interfaces nitrided in NO or N2O ambients is useful to identify the species responsible for the broadening of the peak. In fact, nitridation by NO is mainly responsible for the formation of Si3N moieties at the silicon surface in which silicon atoms are partially oxidized; while nitridation by N2O proceeds with the oxidation of Si – Si backbonds to Si – N bonds, thus resulting in the formation of N(Si(O-)3)3 groups embedded in the oxide. Surface recombination velocity by photocurrent measurements gives evidence that nitridation in N2O is associated with an appreciable co-oxidation, while nitridation in NO is mainly associated with the passivation of interface states. Furthermore N2O and NO nitridation are responsible for different morphologies of the nitrided layers.

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.

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