scholarly journals Diffusion of excessively adsorbed hydrogen atoms on hydrogen terminated Si(100)(2×1) surface

AIP Advances ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 085318
Author(s):  
Kouji Inagaki ◽  
Yoshitada Morikawa ◽  
Hiromasa Ohmi ◽  
Kiyoshi Yasutake ◽  
Hiroaki Kakiuchi
2020 ◽  
Vol 504 ◽  
pp. 144434 ◽  
Author(s):  
Na Cheng ◽  
Ling Zhang ◽  
Yuhang Li ◽  
Liyuan Chen ◽  
Hao Jiang ◽  
...  

1998 ◽  
Vol 513 ◽  
Author(s):  
S. Yu. Zaginaichenko ◽  
Z. A. Matysina ◽  
D. V. Schur ◽  
V. K. Pishuk

ABSTRACTThe theoretical investigation of solubility isosteres of adsorbed hydrogen has been performed for free face (0001) of crystals with hexagonal close-packed lattice A3 of Mg type. The face free energy has been calculated and its dependence on temperature, pressure, hydrogen concentration and character of hydrogen atoms distribution over surface interstitial sites of different type has been defined. The equations of thermodynamic equilibrium and solubility of adsorbed hydrogen have been defined. The plots of isosteres in the region of phase transition from isotropic to anisotropic state have been constructed and it has been established that in anisotropic state the order in distribution of hydrogen atoms over interstitial sites of different type must become apparent. Comparison of the theoretical isosteres with experimental for ruthenium has been carried out, the isotropic-anisotropic state transition can stipulate a stepwise and break-like change in isosteres.


2006 ◽  
Vol 957 ◽  
Author(s):  
Michael Sushchikh ◽  
Vladislav Styrov ◽  
Vladimir Tyutunnikov ◽  
Nick Cordella

ABSTRACTExcitation of a luminescence by highly exothermic chemical reaction on the surface of a luminophore provides a unique opportunity to separate surface luminescence from the bulk luminescence. This enables studies of the electronic properties of the semiconductor surfaces even if the surfaces are of complicate shapes. We have studied heterogeneous chemiluminescence (HCL) of ZnO powders. The luminescence was excited by a release of chemical energy, namely by catalytic recombination of hydrogen atoms. The HCL spectra were compared to the photoluminescence (PL) spectra. The HCL spectra were sensitive to the details of preparation and treatment whereas PL spectra almost did not change. HCL spectra of powder samples pretreated for enhancing “green” luminescence exhibited long-wavelength tail (up to 800 nm) and their maximum was blue-shifted as compared with PL spectra. Different HCL bands forming long-wavelength tail were isolated by changing the temperature of the samples. Additional milling of ZnO led to amplification of the HCL-specific surface bands. Pure ZnO showed neither PL nor HCL; however we were able to observe HCL surface bands with maxima at 610 nm and 730 nm after treatment of the sample in atomic hydrogen atmosphere at 570 K. Remarkably, such treatment did not cause appearance of the PL. The HCL in the presence of atomic hydrogen was steady in time and was caused by an abstraction of adsorbed hydrogen by incident hydrogen atoms, i.e. the reaction followed Eley-Rideal mechanism. The HCL can be utilized for in situ monitoring of the growth and evolution of ZnO in controlled atmosphere.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Zainab N. Jaf ◽  
Hussein A. Miran ◽  
Zhong-Tao Jiang ◽  
Mohammednoor Altarawneh

Abstract Owing to their remarkable characteristics, refractory molybdenum nitride (MoN x )-based compounds have been deployed in a wide range of strategic industrial applications. This review reports the electronic and structural properties that render MoN x materials as potent catalytic surfaces for numerous chemical reactions and surveys the syntheses, procedures, and catalytic applications in pertinent industries such as the petroleum industry. In particular, hydrogenation, hydrodesulfurization, and hydrodeoxygenation are essential processes in the refinement of oil segments and their conversions into commodity fuels and platform chemicals. N-vacant sites over a catalyst’s surface are a significant driver of diverse chemical phenomena. Studies on various reaction routes have emphasized that the transfer of adsorbed hydrogen atoms from the N-vacant sites reduces the activation barriers for bond breaking at key structural linkages. Density functional theory has recently provided an atomic-level understanding of Mo–N systems as active ingredients in hydrotreating processes. These Mo–N systems are potentially extendible to the hydrogenation of more complex molecules, most notably, oxygenated aromatic compounds.


2020 ◽  
Vol 528 ◽  
pp. 146433
Author(s):  
Jessiel Siaron Gueriba ◽  
Wilson Agerico Diño ◽  
Seigi Mizuno ◽  
Michio Okada

1984 ◽  
Vol 17 (3) ◽  
pp. 595-598 ◽  
Author(s):  
B J Verhaar ◽  
J P H W van den Eijnde ◽  
M A J Voermans ◽  
M M J Schaffrath

Sign in / Sign up

Export Citation Format

Share Document