Hydrogen Adsorption of Ruthenium: Isosteres of Solubility of Adsorbed Hydrogen

1998 ◽  
Vol 513 ◽  
Author(s):  
S. Yu. Zaginaichenko ◽  
Z. A. Matysina ◽  
D. V. Schur ◽  
V. K. Pishuk
Keyword(s):  
Phase Transition ◽  
Free Energy ◽  
Theoretical Investigation ◽  
State Transition ◽  
Hydrogen Adsorption ◽  
Adsorbed Hydrogen ◽  
Hydrogen Atoms ◽  
Hexagonal Close Packed ◽  
The Face ◽  
Pressure Hydrogen

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.

Effect of Atomic Hydrogen Concentration in the Study of Adsorption on Graphene

2011 ◽  
Vol 465 ◽  
pp. 211-214
Author(s):  
A.V. Pak ◽  
Nikolay G. Lebedev
Keyword(s):  
Band Structure ◽  
Russian Federation ◽  
Atomic Hydrogen ◽  
Function Method ◽  
Hydrogen Adsorption ◽  
Adsorbed Hydrogen ◽  
Hydrogen Atoms ◽  
Statistical Research ◽  
Graphene Surface ◽  
Quantum Statistical

The results of theoretical quantum-statistical research of atomic hydrogen adsorption on the graphene surface within the framework of the periodic Anderson’s model have been presented. The band structure of graphene with adsorbed hydrogen atoms is calculated by the Green's function method. The work is supported by The Education Ministry of Russian Federation (project No. NK-16(3)).

scholarly journals CoP for hydrogen evolution: implications from hydrogen adsorption

2016 ◽  
Vol 18 (34) ◽  
pp. 23864-23871 ◽  
Author(s):  
Guoxiang Hu ◽  
Qing Tang ◽  
De-en Jiang
Keyword(s):  
Free Energy ◽  
Hydrogen Evolution ◽  
Hydrogen Adsorption ◽  
Hydrogen Atoms ◽  
Free Energy Of Adsorption ◽  
Adsorption Of Hydrogen

Synergistic adsorption of hydrogen atoms on Co and P sites of CoP(111) leads to a nearly neutral free energy of adsorption that is highly conductive to hydrogen evolution.

A Theoretical Study of a H–H Pair on the BCC Fe(100) Surface

2003 ◽  
Vol 10 (04) ◽  
pp. 661-668 ◽  
Author(s):  
E. Gonzalez ◽  
G. Brizuela ◽  
C. Pistonesi ◽  
A. Juan
Keyword(s):  
Electronic Structure ◽  
Nearest Neighbor ◽  
Theoretical Study ◽  
Hydrogen Adsorption ◽  
Theoretical Method ◽  
Adsorbed Hydrogen ◽  
Local Energy ◽  
Hydrogen Atoms ◽  
Adsorption Sites ◽  
Metallic Bond

Hydrogen adsorption on Fe(100) was analyzed using a semiempirical theoretical method. Calculations were performed using a Fe 130 cluster. Adsorption sites for one and two hydrogen atoms on the surface correspond to local energy minima configurations. Changes in the electronic structure of surface Fe atoms were analyzed for the system without hydrogen and with one and two adsorbed hydrogen atoms. Fe atoms close to H weaken their metallic bond. This is due to the formation of H–Fe bonds. Hydrogen influences only its nearest neighbor Fe atoms. The H–H interaction was also analyzed and our results show that H–Fe interaction is much stronger than any possible H–H interaction. No additional decohesion is observed in the Fe–Fe bonds; however, more Fe–Fe bonds are affected.

Evidence for a shear mechanism for the precipitation of γ-zirconium hydride in zirconium

1978 ◽  
Vol 36 (1) ◽  
pp. 658-659
Author(s):  
G.J.C. Carpenter
Keyword(s):  
Elevated Temperature ◽  
Strain Field ◽  
Zirconium Hydride ◽  
Zirconium Atom ◽  
Atom Diffusion ◽  
Solvus Temperature ◽  
Hexagonal Close Packed ◽  
Partial Dislocations ◽  
The Face

In zirconium-hydrogen alloys, rapid cooling from an elevated temperature causes precipitation of the face-centred tetragonal (fct) phase, γZrH, in the form of needles, parallel to the close-packed <1120>zr directions (1). With low hydrogen concentrations, the hydride solvus is sufficiently low that zirconium atom diffusion cannot occur. For example, with 6 μg/g hydrogen, the solvus temperature is approximately 370 K (2), at which only the hydrogen diffuses readily. Shears are therefore necessary to produce the crystallographic transformation from hexagonal close-packed (hep) zirconium to fct hydride.The simplest mechanism for the transformation is the passage of Shockley partial dislocations having Burgers vectors (b) of the type 1/3<0110> on every second (0001)Zr plane. If the partial dislocations are in the form of loops with the same b, the crosssection of a hydride precipitate will be as shown in fig.1. A consequence of this type of transformation is that a cumulative shear, S, is produced that leads to a strain field in the surrounding zirconium matrix, as illustrated in fig.2a.

Peculiarities of high-pressure hydrogen adsorption on Pt catalyzed Cu-BTC metal–organic framework

2021 ◽  
Vol 23 (7) ◽  
pp. 4277-4286
Author(s):  
S. V. Chuvikov ◽  
E. A. Berdonosova ◽  
A. Krautsou ◽  
J. V. Kostina ◽  
V. V. Minin ◽  
...  
Keyword(s):  
High Pressure ◽  
High Pressures ◽  
Hydrogen Adsorption ◽  
Metal Organic Framework ◽  
Pt Catalyst ◽  
Metal Organic ◽  
Pt Catalyzed ◽  
Pressure Hydrogen ◽  
Organic Framework

Pt-Catalyst plays a key role in hydrogen adsorption by Cu-BTC at high pressures.

Extended Gibbs Free Energy and Laplace Pressure of Ordered Hexagonal Close-Packed Spherical Particles: A Wettability Study

Langmuir ◽  
2021 ◽  
Author(s):  
Amir Bayat ◽  
Mahdi Ebrahimi ◽  
Saeed Rahemi Ardekani ◽  
Esmaiel Saievar Iranizad ◽  
Alireza Zaker Moshfegh
Keyword(s):  
Free Energy ◽  
Gibbs Free Energy ◽  
Laplace Pressure ◽  
Spherical Particles ◽  
Hexagonal Close Packed

A novel co-crystallization molecular ferroelectric induced by the ordering of sulphate anions and hydrogen atoms

2018 ◽  
Vol 5 (10) ◽  
pp. 2413-2419 ◽  
Author(s):  
Chang-Feng Wang ◽  
Ji-Xing Gao ◽  
Chao Li ◽  
Chang-Shan Yang ◽  
Jian-Bo Xiong ◽  
...  
Keyword(s):  
Phase Transition ◽  
Ferroelectric Phase Transition ◽  
Ferroelectric Phase ◽  
Dielectric Anomaly ◽  
Hydrogen Atoms

The co-crystallization complex [EG]·[Cu(phen)2·SO4] undergoes a paraelectric–ferroelectric phase transition around 272 K which was confirmed by the observation of a large dielectric anomaly.

(002) facets exposed and controllable thickness of CdS nanobelts drive desirable hydrogen-adsorption free energy (△GH) for boosting visible-light photocatalytic performance

2021 ◽  
Author(s):  
Dejian Yan ◽  
Zhiyong Xue ◽  
Feng Chen ◽  
Xia Liu ◽  
Zhenhua Yang ◽  
...  
Keyword(s):  
Free Energy ◽  
Visible Light ◽  
Environmental Pollution ◽  
Economically Disadvantaged ◽  
Photocatalytic Performance ◽  
Hydrogen Adsorption ◽  
Co Catalysts ◽  
Adsorption Free Energy ◽  
Cds Nanobelts ◽  
Visible Light Photocatalytic

In order to obtain the high photocatalytic performance, co-catalysts loading is the most commonly used, which is economically disadvantaged and environmental pollution. Here, we combine the strategy of controllable thickness...

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