X-ray Diffraction Studies of Free-Standing Electrodeposited Cu-patterns

2004 ◽  
Vol 6 (10) ◽  
pp. 828-832
Author(s):  
K. Pantleon ◽  
H.M. Jensen ◽  
M.A.J. Somers
Keyword(s):  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray

scholarly journals The Synergistic Effects of Alloying on the Performance and Stability of Co3Mo and Co7Mo6 for the Electrocatalytic Hydrogen Evolution Reaction

Hydrogen ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 11-21
Author(s):  
Youyi Sun ◽  
Alexey Y. Ganin
Keyword(s):  
Hydrogen Evolution ◽  
Synergistic Effects ◽  
Alkaline Media ◽  
Price Of Stability ◽  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray ◽  
Current Decay ◽  
Earth Abundant ◽  
Current Densities

Metal alloys have become a ubiquitous choice as catalysts for electrochemical hydrogen evolution in alkaline media. However, scarce and expensive Pt remains the key electrocatalyst in acidic electrolytes, making the search for earth-abundant and cheaper alternatives important. Herein, we present a facile and efficient synthetic route towards polycrystalline Co3Mo and Co7Mo6 alloys. The single-phased nature of the alloys is confirmed by X-ray diffraction and electron microscopy. When electrochemically tested, they achieve competitively low overpotentials of 115 mV (Co3Mo) and 160 mV (Co7Mo6) at 10 mA cm−2 in 0.5 M H2SO4, and 120 mV (Co3Mo) and 160 mV (Co7Mo6) at 10 mA cm−2 in 1 M KOH. Both alloys outperform Co and Mo metals, which showed significantly higher overpotentials and lower current densities when tested under identical conditions, confirming the synergistic effect of the alloying. However, the low overpotential in Co3Mo comes at the price of stability. It rapidly becomes inactive when tested under applied potential bias. On the other hand, Co7Mo6 retains the current density over time without evidence of current decay. The findings demonstrate that even in free-standing form and without nanostructuring, polycrystalline bimetallic electrocatalysts could challenge the dominance of Pt in acidic media if ways for improving their stability were found.

Residual stresses in chemical vapor deposition free-standing diamond films by X-ray diffraction analyses

2000 ◽  
Vol 288 (2) ◽  
pp. 217-222 ◽  
Author(s):  
O Durand ◽  
R Bisaro ◽  
C.J Brierley ◽  
P Galtier ◽  
G.R Kennedy ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Residual Stresses ◽  
Vapor Deposition ◽  
Diamond Films ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray

Control of Crystallinity of Hydroxyapatite Sheet

2013 ◽  
Vol 583 ◽  
pp. 47-50 ◽  
Author(s):  
Masanobu Kusunoki ◽  
Taiyo Matsuda ◽  
Naoki Fujita ◽  
Yasuhiro Sakoishi ◽  
Ryou Iguchi ◽  
...  
Keyword(s):  
Cell Culture ◽  
Annealing Temperature ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray ◽  
Electric Oven ◽  
Diffraction Peaks ◽  
Conventional Annealing

A technique to control the crystallinity of hydroxyapatite (HA) was investigated for applications such as dentistry, regenerative medicine, cell culture scaffolding, and bio-sensors. An amorphous HA film was first produced by pulsed laser deposition. After deposition, it was separated from a substrate as a free-standing sheet. Annealing was then performed to control the crystallinity of the sheet. It was found that conventional annealing in an electric oven was not suitable for HA sheets, because it led to curling and cracking. Since such problems were assumed to be caused by thermal stress, annealing was next carried out with the HA sheet enclosed in HA powder in the center of a metal capsule. This method allowed annealing to be successfully carried out without causing any curling or cracking. Uniform pieces with dimensions of 10 mm × 10 mm cut from a large HA sheet were annealed at temperatures of 200 to 800 ºC and then examined using X-ray diffraction. It was found that the intensity of the diffraction peaks associated with crystalline HA changed with annealing temperature, and that the strongest peaks were observed for the sample annealed at 500 ºC. These results indicate that the crystallinity of the HA sheet can be controlled using the proposed method.

Free-standing Smectic LC Elastomer Films

2001 ◽  
Vol 709 ◽  
Author(s):  
C. Tolksdorf ◽  
R. Zentel ◽  
R. Köhler ◽  
U. Dietrich ◽  
M. Lösche ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Liquid Crystalline ◽  
Film Plane ◽  
X Ray Diffraction ◽  
Free Standing ◽  
Layer Spacing ◽  
X Ray ◽  
Precursor Polymer ◽  
Layer Structures ◽  
Freely Suspended

ABSTRACTWe probe the mesophase transitions and layer structures in thin ordered smectic liquid crystalline elastomer films by means of x-ray diffraction and optical microscopy. Oriented elastomer films of submicrometer thickness are produced by crosslinking freely suspended smectic polymer films. After crosslinking, the mesomorphism is similar to that of the precursor polymer. Smectic layers align parallel to the film plane. The layer spacing increases with temperature in the SmC* phase while it decays above the SmC*-SmA transition.

Perspectives and limitations of symmetric X-ray Bragg reflections for inspecting polytypism in nanowires

2016 ◽  
Vol 23 (2) ◽  
pp. 487-500 ◽  
Author(s):  
Martin Köhl ◽  
Philipp Schroth ◽  
Tilo Baumbach
Keyword(s):  
Statistical Significance ◽  
Large Set ◽  
X Ray Diffraction ◽  
Free Standing ◽  
Time Resolved ◽  
X Ray ◽  
Transmission Electron ◽  
Gaas Nanowires ◽  
High Statistical Significance ◽  
Proper Interpretation

X-ray diffraction, possibly time-resolved during growth or annealing, is an important technique for the investigation of polytypism in free-standing nanowires. A major advantage of the X-ray diffraction approach for adequately chosen beam conditions is its high statistical significance in comparison with transmission electron microscopy. In this manuscript the interpretation of such X-ray intensity distribution is discussed, and is shown to be non-trivial and non-unique given measurements of the [111]cor [333]creflection of polytypic nanowires grown in the (111)cdirection. In particular, the diffracted intensity distributions for several statistical distributions of the polytypes inside the nanowires are simulated and compared. As an example, polytypic GaAs nanowires are employed, grown on a Si-(111) substrate with an interplanar spacing of the Ga (or As) planes in the wurtzite arrangement that is 0.7% larger than in the zinc blende arrangement along the (111)cdirection. Most importantly, ambiguities of high experimental relevance in the case of strongly fluctuating length of the defect-free polytype segments in the nanowires are demonstrated. As a consequence of these ambiguities, a large set of deviations from the widely used Markov model for the stacking sequences of the nanowires cannot be detected in the X-ray diffraction data. Thus, the results here are of high relevance for the proper interpretation of such data.

ZnO Films Deposited on Various Diamond Film Substrates with Different Surface Roughness

2011 ◽  
Vol 287-290 ◽  
pp. 2347-2350
Author(s):  
Rong Fan ◽  
Lin Jun Wang ◽  
Jian Huang ◽  
Ke Tang ◽  
Ji Jun Zhang ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Roughness ◽  
Diamond Film ◽  
Zno Thin Films ◽  
Zno Films ◽  
X Ray Diffraction ◽  
Free Standing ◽  
Axis Orientation ◽  
X Ray ◽  
Force Microscopy

ZnO thin films were deposited by radio frequency (R. F.) magnetron sputtering on various diamond film substrates with different surface roughness. The influence of surface roughness on structural properties and surface morphology of ZnO thin films was investigated by X-ray diffraction (XRD) and atom force microscopy (AFM), respectively. Only on the nanocrystalline and free-standing diamond substrates, ZnO films with preferential c-axis orientation and smooth surface were obtained.

X-ray diffraction investigations of adherent and free standing TiN coatings deposited by magnetron sputtering

1990 ◽  
Vol 41 (3) ◽  
pp. 377-388 ◽  
Author(s):  
V. Valvoda ◽  
R. Kužel ◽  
L. Dobiášová ◽  
R. Černý ◽  
V. Poulek ◽  
...  
Keyword(s):  
Magnetron Sputtering ◽  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray ◽  
Tin Coatings

Electrochemical synthesis and properties of layer-structured polypyrrole/montmorillonite nanocomposite films

2010 ◽  
Vol 25 (4) ◽  
pp. 658-664 ◽  
Author(s):  
Chang-An Wang ◽  
Keyu Chen ◽  
Yong Huang ◽  
Huirong Le
Keyword(s):  
Deposition Time ◽  
Composite Films ◽  
Nanocomposite Films ◽  
Nanoindentation Test ◽  
Test Results ◽  
X Ray Diffraction ◽  
Free Standing ◽  
Sem Images ◽  
X Ray ◽  
Scanning Electron

Layer-structured polypyrrole/montmorillonite (PPy/MMT) naoncomposite films were synthesized by the electrodeposition method. The fabricated free-standing films consist of about 0∼2 wt% Na+-montmorillonite (NMMT). The thickness of films could be controlled by deposition time. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to observe the microstructure of the films. After MMT was introduced into the PPy matrix, the interspace between PPy chains decreased, according to the XRD results. The layered structure of the films was observed from the SEM images. Tensile and nanoindentation test results showed that the mechanical properties of the composite films were improved at low clay loading. The electrical conductivity of the films with 1.2 wt% MMT loading was increased from 3.6 to 51 S/cm, probably because of the restricted growth of PPy chains in the interspace of MMT layers.

scholarly journals Surface morphology smoothing of a 2 inch-diameter GaN homoepitaxial layer observed by X-ray diffraction topography

RSC Advances ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 1878-1882
Author(s):  
Jaemyung Kim ◽  
Okkyun Seo ◽  
Satoshi Hiroi ◽  
Yoshihiro Irokawa ◽  
Toshihide Nabatame ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Grazing Incidence ◽  
Incidence Geometry ◽  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray ◽  
Grazing Incidence Geometry ◽  
Morphology Changes

We investigated the surface morphology changes in a 2 inch-diameter, c-plane, free-standing GaN wafer using X-ray diffraction topography in a grazing-incidence geometry.

Role of the strained substrate in the x-ray diffraction of free-standing epitaxial nanostructures under grazing incidence conditions

2019 ◽  
Vol 99 (19) ◽  
Author(s):  
S. Lazarev ◽  
P. Schroth ◽  
D. Grigoriev ◽  
M. Riotte ◽  
T. Slobodskyy ◽  
...  
Keyword(s):  
Grazing Incidence ◽  
X Ray Diffraction ◽  
Free Standing ◽  
X Ray
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