Relation between grazing incident X-ray diffraction and surface defects in silicon doped GaAs

2010 ◽  
Vol 405 (9) ◽  
pp. 2185-2188
Author(s):  
J.A. Villada ◽  
S. Jiménez-Sandoval ◽  
M. López-López ◽  
L. Baños ◽  
M.E. Rodríguez-García
Keyword(s):  
Surface Defects ◽  
X Ray Diffraction ◽  
X Ray ◽  
Silicon Doped

scholarly journals Photovoltaic Characteristics of CH3NH3PbI3 Perovskite Solar Cells Added with Ethylammonium Bromide and Formamidinium Iodide

Coatings ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 410 ◽  
Author(s):  
Kousuke Nishi ◽  
Takeo Oku ◽  
Taku Kishimoto ◽  
Naoki Ueoka ◽  
Atsushi Suzuki
Keyword(s):  
Surface Defects ◽  
Perovskite Solar Cells ◽  
Ambient Air ◽  
X Ray Diffraction ◽  
Perovskite Layer ◽  
X Ray ◽  
Lattice Constants ◽  
Crystal Orientations ◽  
Crystallite Sizes ◽  
Photovoltaic Characteristics

Photovoltaic characteristics of solar cell devices in which ethylammonium (EA) and formamidinium (FA) were added to CH3NH3PbI3 perovskite photoactive layers were investigated. The thin films for the devices were deposited by an ordinary spin-coating technique in ambient air, and the X-ray diffraction analysis revealed changes of the lattice constants, crystallite sizes and crystal orientations. By adding FA and EA, surface defects of the perovskite layer decreased, and the photoelectric parameters were improved. In addition, the highly (100) crystal orientations and device stabilities were improved by the EA and FA addition.

scholarly journals Mechanism of Floater Formation in the Mold during Continuous Casting of Ti-Stabilized Austenitic Stainless Steels

Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 635 ◽  
Author(s):  
Zhuo Chen ◽  
Min Li ◽  
Xufeng Wang ◽  
Shengping He ◽  
Qian Wang
Keyword(s):  
Continuous Casting ◽  
Stainless Steels ◽  
Mold Flux ◽  
Surface Defects ◽  
Austenitic Stainless Steels ◽  
Coordinated Control ◽  
Bearing Steel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mold Slag

During the continuous casting (CC) of Ti-bearing steel, a steel lump can solidify in the mold (i.e., floater steel) more easily than in the Ti-free steels. This causes severe surface defects or even a breakout. We have examined the mechanisms of floater formation during the CC of 321 stainless steel by analyzing the inclusions in the floater steel and in the 321 steel that was sampled from the mold. Additionally, we calculated the disregistry between the metallic phases and common inclusions. The mineralogy and morphology of the inclusions were examined while using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Thermodynamic calculations on the TixOy inclusions at different oxygen potentials were performed while using FactSage 7.2. Using this approach, we determined that ferrite nucleates grow on TiN and MgO inclusions following solidification, which then form micro-aggregates as a result of dynamic collisions and alliances. Analysis of the mold slag from the metallurgy stage indicated that altering the basicity and properties of the mold flux systematically might minimize the reaction between the slag and steel, which would achieve a coordinated control over lubrication and heat transfer.

X-ray-diffraction measurements from imperfect GaAs crystals: Evidence for near-surface defects

1990 ◽  
Vol 42 (8) ◽  
pp. 5093-5099 ◽  
Author(s):  
R. Bloch ◽  
D. Bahr ◽  
J. Olde ◽  
L. Brügemann ◽  
W. Press
Keyword(s):  
Surface Defects ◽  
X Ray Diffraction ◽  
Near Surface ◽  
X Ray

scholarly journals Photoluminescent Enhancement by Effect of Incorporation Nickel in ZnO Films Grown

2021 ◽  
Vol 6 (5) ◽  
pp. 177-180
Author(s):  
Delfino R. Gutiérrez ◽  
Tomás Díaz-Becerril ◽  
Godofredo García-Salgado ◽  
Antonio Coyopol-Solís ◽  
Enrique Rosendo-Andrés ◽  
...  
Keyword(s):  
Oxygen Vacancies ◽  
Surface Defects ◽  
Chemical Vapor ◽  
Green Emission ◽  
Zno Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Green Emission Band ◽  
The Right ◽  
Hot Filament

Microstructured films of undoped zinc oxide (ZnO) and ZnO doped with nickel (ZnO:Ni) were grown by hot filament chemical vapor deposition (HFCVD) technique on Si (100) substrates at 500 °C. Pellets of ZnO and ZnO:NiO as oxidant agenst were used. A shift to the right around 0.17 degree of the X-Ray Diffraction pattern of the ZnO:Ni film was observed with respect to undoped ZnO films. Morphologically by Scanning Electron Microscopy was noticed a Core-Shell type growth in ZnO undoped and a nanostructured type (Nano-wire) in ZnO doped with Ni. Photoluminescence measurements showed an increase in the intensity of the green emission band of ZnO:Ni. It was attributed to defects of oxygen vacancies (VO), zinc vacancies (VZn), zinc interstitials (Zni), oxygen interstitials (Oi), and oxygen vacancies complex (VO complex) in the structure of the film. The incorporation of Ni atoms in the ZnO structure stresses the crystal lattice, leaving behind a large number of surface defects that increase the emission of PL.

scholarly journals Evaluation of usage-induced degradation of different endodontic file systems

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shekhar Bhatia ◽  
Venkatesh Nagendrababu ◽  
Ove A. Peters ◽  
Amr Fawzy ◽  
Umer Daood
Keyword(s):  
Photoelectron Spectroscopy ◽  
Surface Defects ◽  
File System ◽  
File Systems ◽  
Passive Layer ◽  
Binding Energies ◽  
X Ray Diffraction ◽  
X Ray ◽  
Before And After

AbstractTo evaluate structural profiles and mechanical behaviour of WaveOne Gold (WOG), Twisted File Adaptive (TFA) and XP-endo shaper (XPS) instruments after root canal preparation. Standardized in vitro shaping was performed in presence of 5.25% sodium hypochlorite. File morphology was analyzed using scanning electron microscopy; X-ray diffraction analysis was performed before and after use along with Raman spectroscopy. Nanoindentation was carried out to characterize surface topography. Ni2+ release was measured at 1, 3, 5 and 7 days. X-ray photoelectron spectroscopy (XPS) analysis was done before and after use. After allocating scan line shifts like in WOG, mechanical deformation was shown using first order polynomials. XPS file system showed minimal grooves on surface. SEM of WOG instrument showed scraping surface defects. Hardness varied from 8.11 ± 0.99 GPa in TFA system to 6.7 ± 1.27 GPa and 4.06 ± 4.1 GPa in XPS and WOG. Ni2+ concentration from WOG was 171.2 μg/L. Raman peak at 540–545 cm−1 is attributed to Cr2O3. High resolution of Ti 2p spectrum show distinctive peaks with binding energies dominating in WOG, XPS and TFA file system. XRD exhibited NiTi phases with diffraction peaks. WOG files showed more surface deterioration and less passive layer formation as compared to TFA and XPS systems.

SrTiO3 films on platinized (0001) Al2O3: Characterization of texture and nonstoichiometry accommodation

2004 ◽  
Vol 19 (5) ◽  
pp. 1477-1486 ◽  
Author(s):  
Dmitri O. Klenov ◽  
Troy R. Taylor ◽  
Susanne Stemmer
Keyword(s):  
Surface Defects ◽  
X Ray Diffraction ◽  
Pt Electrode ◽  
Lattice Match ◽  
Planar Defects ◽  
X Ray ◽  
Grain Sizes ◽  
Transmission Electron ◽  
Pt Films

Transmission electron microscopy and x-ray diffraction were used to study SrTiO3 films grown on platinized (0001) Al2O3 substrates. The Pt films were epitaxial with an orientation relationship described by (111)Pt‖(0001)Al2O3 and [110]Pt‖[10¯10]Al2O3. SrTiO3 films with two different Sr to Ti ratios, 1.02 and 1.4, were deposited by radio-frequency magnetron sputtering. In the film with a large amount of Sr excess, the grain sizes were smaller and a high density of planar defects was observed. The films were predominantly (111) textured, but a weaker (110) texture component was also found, independent of stoichiometry. While the (111) texture could be explained with the excellent lattice match with (111) Pt, the (110) textured grains had a large mismatch with the Pt electrode. We propose that the presence of the (110) oriented grains is due to nucleation at Pt surface defects. Planar defects in the films with a large amount of Sr excess served to accommodate the nonstoichiometry. Comparison with homoepitaxial SrTiO3 films showed that the density of planar defects in the SrTiO3 films on (111)Pt/Al2O3 is insufficient to accommodate all the excess Sr. The influence of the film microstructure on the dielectric properties is also discussed.

scholarly journals Synthesis and catalytic properties of a novel copper- and manganese-substituted cerium dioxide for benzene remediation

2020 ◽  
pp. 174751982094588
Author(s):  
Jae Hwan Yang ◽  
Jeong Hyun You
Keyword(s):  
Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Environmental Remediation ◽  
Surface Defects ◽  
Superior Performance ◽  
Isomorphous Substitution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Areas ◽  
Transmission Electron

Catalysts based on inexpensive and abundant transition metals are necessary for effective environmental remediation. In this study, a series of CuMn-CeO2 catalysts is synthesized by a simple coprecipitation method. The properties of the as-prepared catalysts are characterized by X-ray diffraction, Brunauer–Emmett–Teller analysis, scanning electron microscopy–energy-dispersive spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The introduction of dopants results in rougher surfaces with greater surface areas and pore volumes as well as more surface defects. Furthermore, the dopant-added catalysts exhibit higher activities for benzene oxidation, as the temperature required for 90% benzene removal with Cu4Mn1-CeO2 (656 K) was 231 K lower than that required with CeO2. The superior performance of the dopant-added CeO2 catalyst is attributed to the generation of defect-rich surfaces due to the isomorphous substitution of Cu and Mn in the crystal lattice of CeO2.

The Effect of Molecular Weight on the Structure and Properties of PAN Precursor

2013 ◽  
Vol 781-784 ◽  
pp. 2609-2613 ◽  
Author(s):  
Xue Lin ◽  
Cheng Guo Wang ◽  
Mei Jie Yu ◽  
Zhi Tao Lin
Keyword(s):  
Molecular Weight ◽  
Surface Defects ◽  
Exothermic Reaction ◽  
Interlayer Spacing ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Scanning Electron ◽  
Effect Of Surface

The effect of molecular weight on the structure and properties of PAN precursor was studied by the combination of scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC), etc. With the molecular weight increasing, the grooves on the surface become deeper and rougher, the interlayer spacing and crystallite size increase, and the exothermic reaction occurred later. The strength and breaking extension of PAN precursors increase gradually with the molecular weight increasing. The effect of molecular weight is greater than the effect of surface defects on strength for PAN precursor of high molecular weight.

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