Structural stability and hydrogen diffusion in alloys

ABSTRACTIn this work the mechanism of hydrogen incorporation and structural stability of a-Si:H films deposited by LF 55 kHz glow discharge in a wide range of technological parameters have been investigated. The analysis of plasma emission spectra and microstructure of films measured by IR spectroscopy and atomic force microscopy were carried out. It was shown that hydrogen desorption controls the growth rate in a wide range of substrate temperature (40–325°C ) and at low values of LF power (50–200W). At the same time the abnormal increase of hydrogen content due to ion-molecule surface reactions with the increase of substrate temperature was observed. The kinetics of hydrogen diffusion and thermodynamics of defect formation in a-SiH films were determined from modeling of differential scanning calorimetry data. It is concluded that the mechanism of hydrogen incorporation leads to formation of strong Sill bonds in the material bulk and to increase of structural stability with the increase of substrate temperature despite of the increase of hydrogen content.

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Effects of Mo alloying on stability and diffusion of hydrogen in the Nb16H phase: a first-principles investigation

RSC Advances ◽

10.1039/c9ra03401c ◽

2019 ◽

Vol 9 (34) ◽

pp. 19495-19500 ◽

Cited By ~ 3

Author(s):

Dianhui Wang ◽

Yang Wu ◽

Zhenzhen Wan ◽

Feng Wang ◽

Zhongmin Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Structural Stability ◽

First Principles ◽

Hydrogen Diffusion ◽

First Principles Calculations ◽

Elastic Band ◽

Diffusion Behavior ◽

Band Method ◽

And Diffusion ◽

Diffusion Of Hydrogen

First-principles calculations and climbing-image nudged elastic band method were used to investigate the effects of Mo alloying on the structural stability, mechanical properties, and hydrogen-diffusion behavior of Nb.

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Time-resolved high-resolution electron microscopy of structural stability in mgo clusters

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165823 ◽

1996 ◽

Vol 54 ◽

pp. 672-673

Author(s):

T. Kizuka ◽

N. Tanaka

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Magnesium Oxide ◽

Structural Stability ◽

High Resolution Electron Microscopy ◽

Video Tape ◽

Solid State Physics ◽

Time Resolved ◽

Resolution Electron ◽

Structural And Functional Properties

Structure and stability of atomic clusters have been studied by time-resolved high-resolution electron microscopy (TRHREM). Typical examples are observations of structural fluctuation in gold (Au) clusters supported on silicon oxide films, graphtized carbon films and magnesium oxide (MgO) films. All the observations have been performed on the clusters consisted of single metal element. Structural stability of ceramics clusters, such as metal-oxide, metal-nitride and metal-carbide clusters, has not been observed by TRHREM although the clusters show anomalous structural and functional properties concerning to solid state physics and materials science.In the present study, the behavior of ceramic, magnesium oxide (MgO) clusters is for the first time observed by TRHREM at 1/60 s time resolution and at atomic resolution down to 0.2 nm.MgO and gold were subsequently deposited on sodium chloride (001) substrates. The specimens, single crystalline MgO films on which Au particles were dispersed were separated in distilled water and observed by using a 200-kV high-resolution electron microscope (JEOL, JEM2010) equipped with a high sensitive TV camera and a video tape recorder system.

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