Adsorption and dissociation of O2 on MoSe2 and MoTe2 monolayers: ab initio study

2014 ◽  
Vol 28 (28) ◽  
pp. 1450195 ◽  
Author(s):  
X. F. Zhu ◽  
L. Wang ◽  
L. F. Chen
Keyword(s):  
Spin Polarization ◽  
Density Functional ◽  
Dissociative Adsorption ◽  
Generalized Gradient ◽  
Long Distance ◽  
Electronic Density ◽  
Functional Theory ◽  
Adsorption Sites ◽  
D Orbitals ◽  
Adsorption And Dissociation

Adsorption and dissociation of O 2 molecule on the MoSe 2 and MoTe 2 monolayers are studied by using density functional theory (DFT) within the generalized gradient approximation (GGA) and a supercell approach. The physisorbed O 2 molecule on MoSe 2 and MoTe 2 with a magnetic moment (MM) close to that for an isolated O 2 molecule has small adsorption energy and long distance from the surface. The dissociative adsorption of configuration R5(R6) is the most stable adsorption site, whereas the chemisorption of O 2 is unfavorable at all adsorption sites. The dissociative adsorption of configuration R4 induces dramatic changes of electronic structures and localized spin polarization both for monolayer MoSe 2 and MoTe 2. The analysis of electronic density of states (DOSs) shows that the contribution of spin polarization is mainly from the hybridization between O –p, Se(Te) –p and Mo –d orbitals.

ADSORPTION AND DISSOCIATION OF O2 ON Ti3Al (0001) STUDIED BY FIRST-PRINCIPLES

2015 ◽  
Vol 22 (04) ◽  
pp. 1550053 ◽  
Author(s):  
LI-JING WEI ◽  
JIAN-XIN GUO ◽  
XIU-HONG DAI ◽  
YING-LONG WANG ◽  
BAO-TING LIU
Keyword(s):  
First Principles ◽  
Density Functional ◽  
Structure Optimization ◽  
Oxygen Molecule ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Adsorption Sites ◽  
Generalized Gradient Approximation ◽  
Junction Site ◽  
Adsorption And Dissociation

The adsorption and dissociation of oxygen molecule on Ti 3 Al (0001) surface have been investigated by density functional theory (DFT) with the generalized gradient approximation (GGA). All possible adsorption sites including nine vertical and fifteen parallel sites of O 2 are considered on Ti 3 Al (0001) surface. It is found that all oxygen molecules dissociate except for three vertical adsorption sites after structure optimization. This indicates that oxygen molecules prefer to dissociate on the junction site between Ti and Al atoms. Oxygen atoms coming from dissociation of oxygen molecule tend to occupy the most stable adsorption sites of the Ti 3 Al (0001) surface. The distance of O – O is related to the surface dissociation distance of Ti 3 Al (0001) surface. The valence electron localization function (ELF) and projected density of states (DOS) show that the bonds of O – O are breakaway at parallel adsorption end structures.

Investigation, using density function theory, of coverage of the kaolinite (001) surface during hydrogen adsorption

Clay Minerals ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 393-402 ◽  
Author(s):  
Jian Zhao ◽  
Wei Gao ◽  
Zhi-Gang Tao ◽  
Hong-Yun Guo ◽  
Man-Chao He
Keyword(s):  
Density Functional ◽  
Hydrogen Adsorption ◽  
Function Theory ◽  
Lattice Relaxation ◽  
Electronic Density ◽  
Functional Theory ◽  
Adsorption Sites ◽  
Coverage Dependence ◽  
Hydrogen Molecules ◽  
Wide Range

ABSTRACTKaolinite can be used for many applications, including the underground storage of gases. Density functional theory was employed to investigate the adsorption of hydrogen molecules on the kaolinite (001) surface. The coverage dependence of the adsorption sites and energetics was studied systematically for a wide range of coverage, Θ (from 1/16 to 1 monolayer). The three-fold hollow site is the most stable, followed by the bridge, top-z and top sites. The adsorption energy of H2 decreased with increasing coverage, thus indicating the lower stability of surface adsorption due to the repulsion of neighbouring H2 molecules. The coverage has obvious effects on hydrogen adsorption. Other properties of the H2/kaolinite (001) system, including the lattice relaxation and changes of electronic density of states, were also studied and are discussed in detail.

Structural, Elastic and Electronic Properties of γ˝ Phase Precipitate in Mg-Gd-Zn Alloy

2019 ◽  
Vol 41 (6) ◽  
pp. 932-932
Author(s):  
Mengmeng Wu Mengmeng Wu ◽  
Rongkai Pan Rongkai Pan ◽  
Jilei Liang Jilei Liang ◽  
Guohai Zhou Guohai Zhou ◽  
Li Ma and Chunyu Zhang Li Ma and Chunyu Zhang
Keyword(s):  
Density Functional ◽  
Elastic Anisotropy ◽  
Poisson Ratio ◽  
Covalent Bond ◽  
Generalized Gradient ◽  
Electronic Density ◽  
Functional Theory ◽  
Full Relaxation ◽  
Principle Density Functional Theory ◽  
Zn Alloy

The γ˝ phase (Mg4GdZn) precipitate in Mg-Gd-Zn alloy was calculated via first-principle density functional theory within the generalized gradient approximation. Through structure optimization of full relaxation, the lattice parameters were theoretically obtained, and the calculated Mg4GdZn is the most energetically stable in view of the formation energy. Independent elastic constants were also calculated, illustrating the calculated Mg4GdZn is mechanically stable. The shear modulus, polycrystalline bulk modulus, Poisson ratio, and Young’s modulus of Mg4GdZn were calculated via the Voigt-Reuss-Hill approximation. Elastic anisotropy and ductility were analyzed in details. Seen from their charge density distribution and electronic density of states, both metallic bond and covalent bond were found in Mg4GdZn.

First principle calculations of hydrogen sulfide adsorption and dissociation on pure Pd (111) and Au (111), and alloy Pd/Au (111) and Au/Pd (111) surfaces

2014 ◽  
Vol 13 (08) ◽  
pp. 1450065 ◽  
Author(s):  
Na Liu ◽  
Xue-Ye Wang ◽  
Ya-Li Wan
Keyword(s):  
Hydrogen Sulfide ◽  
Metal Surfaces ◽  
Density Functional ◽  
Generalized Gradient ◽  
Dissociation Process ◽  
Functional Theory ◽  
Band Center ◽  
Plane Wave Method ◽  
Adsorption Energies ◽  
Adsorption And Dissociation

The hydrogen sulfide adsorption and dissociation on pure Pd (111) and Au (111), alloy Pd / Au (111) and Au / Pd (111) surfaces have been investigated using the pseudo-potential plane wave method within the generalized-gradient approximation density functional theory (GGA+DFT). The results show that H 2 S tends to be adsorbed on top site, HS prefers to locate on bridge site, and the S and H locate on fcc site on various surfaces. Compared the adsorption of sulfur-containing species and hydrogen on pure and alloy metal surfaces, a similar trend of adsorption energies on the metal surfaces ( Pd / Au (111) > Pd (111) > Au (111) > Au / Pd (111)) is found. In addition, the dissociation process on the Pd (111) and Pd / Au (111) surfaces is predicted to be exothermic. However, on Au (111) and Au / Pd (111), the dissociation process is endothermic. The work reveals that H 2 S dissociation is more likely to happen on Pd / Au (111) surface. Finally, the adsorption energies of adsorbate on metal surfaces have strong correlation with the d-band center. The d-band center moves away from the Fermi level, and the adsorption energy decreases. According to the LDOS analysis, the inner Au atoms of Pd / Au (111) can enhance the top-layer d-band intensity, whereas the inner Pd atoms of Au / Pd (111) cause the opposite effect. The further electronic state analysis reveals the interaction between H 2 S and metal surfaces.

PLANE-WAVE PSEUDOPOTENTIAL DENSITY FUNCTIONAL THEORY PERIODIC SLAB CALCULATIONS OF NO ADSORPTION ON Ag(001) SURFACE

2010 ◽  
Vol 09 (04) ◽  
pp. 701-709
Author(s):  
H. AGHAIE ◽  
M. R. GHOLAMI ◽  
F. KHAZALI ◽  
K. ZARE ◽  
M. MONAJJEMI ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Density Functional Theory ◽  
Plane Wave ◽  
Density Functional ◽  
Hollow Site ◽  
Generalized Gradient ◽  
No Adsorption ◽  
Functional Theory ◽  
Adsorption Sites ◽  
Generalized Gradient Approximation

Plane-wave pseudopotential density functional theory (DFT) periodic slab calculations were performed using the generalized gradient approximation (GGA) to investigate the adsorption of nitric oxide (NO) on the (001) surface of Ag . We examined three different adsorption sites perpendicular with respect to the surface and a position that the axis of NO molecule was tilted from the upright. The adsorption of NO in the fourfold hollow site was favored, with a binding energy of 45.47 kJ/mol.

FIRST-PRINCIPLES STUDY OF ADSORPTION OF CN ON Cu(111)

2007 ◽  
Vol 06 (03) ◽  
pp. 523-529 ◽  
Author(s):  
WENZHEN LAI ◽  
HONG RAN ◽  
DAIQIAN XIE
Keyword(s):  
First Principles ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Stationary Points ◽  
Plane Wave Expansion ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Adsorption Sites ◽  
Parallel Mode ◽  
Pseudo Potential

The adsorption of CN on Cu (111) has been investigated using density functional theory calculations based on plane-wave expansion and pseudo-potential treatment. Calculations within the generalized gradient approximation predicted a preference for CN in the fcc C -down site. No stationary points corresponding to pure parallel mode were found. But the tilted mode was found to be achievable. The calculated vibrational frequencies of CN were used to correctly discriminate between the adsorption sites.

Structures and electronic properties of WmCunH2 (m+n ≤ 7) clusters

2018 ◽  
Vol 32 (20) ◽  
pp. 1850209
Author(s):  
Zhicheng Yu ◽  
Xiurong Zhang ◽  
Kun Gao ◽  
Peiying Huo
Keyword(s):  
Hydrogen Storage ◽  
Electronic Properties ◽  
Density Functional ◽  
Hydrogen Adsorption ◽  
Generalized Gradient ◽  
Functional Theory ◽  
High Thermodynamic Stability ◽  
Analysis Of Stability ◽  
Ground State Structures ◽  
Adsorption And Dissociation

Geometric and electronic structures of W[Formula: see text]Cu[Formula: see text]H2 (m + n [Formula: see text] 7) clusters have been systematically calculated by density functional theory (DFT) at the generalized gradient approximation (GGA) level for ground-state structures. For all W–Cu clusters, H atoms prefer to attach to W atoms in this system during adsorption. And more electrons transfer from H atom to W atom with the growth of the size of the cluster which benefits the hydrogen storage. Analysis of stability properties and electronic properties shows that hydrogen adsorption and dissociation process take place more efficiently at the W2Cu3H2 cluster than the others. Due to high thermodynamic stability and adsorption energy of W5CuH2 cluster among W[Formula: see text]Cu[Formula: see text]H2 (m + n [Formula: see text] 7) clusters, W5Cu is more suitable for hydrogen storage.

Dissociative adsorption of O2 on strained Pt(111)

2018 ◽  
Vol 20 (26) ◽  
pp. 17927-17933 ◽  
Author(s):  
Tiantian Xue ◽  
Chao Wu ◽  
Xiangdong Ding ◽  
Jun Sun
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Dissociative Adsorption ◽  
Functional Theory ◽  
Adsorption And Dissociation

The adsorption and dissociation of O2 and the adsorption of O* adatoms over strained Pt(111) surfaces have been systematically studied using density functional theory calculations.

Coverage dependent water dissociative adsorption on Fe(110) from DFT computation

2015 ◽  
Vol 17 (14) ◽  
pp. 8811-8821 ◽  
Author(s):  
Shaoli Liu ◽  
Xinxin Tian ◽  
Tao Wang ◽  
Xiaodong Wen ◽  
Yong-Wang Li ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Ab Initio ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Dissociative Adsorption ◽  
Functional Theory ◽  
Atomistic Thermodynamics ◽  
Adsorption And Dissociation

Using density functional theory calculations and ab initio atomistic thermodynamics, H2O adsorption and dissociation on the Fe(110) p(4 × 4) surface at different coverages have been computed.

Structure stability and magnetic properties of WnH2 (n =7–12) clusters

2015 ◽  
Vol 29 (27) ◽  
pp. 1550184 ◽  
Author(s):  
Xiang-Yu Zheng ◽  
Xiu-Rong Zhang ◽  
Ling-Ling Zhang ◽  
Gao-Kang Hu
Keyword(s):  
Magnetic Properties ◽  
Ground State ◽  
Density Functional ◽  
Structure Stability ◽  
Density Of State ◽  
Generalized Gradient ◽  
Electronic Density ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Ground State Structures

In this paper, the structure and magnetic properties of WnH2 (n = 7–12) clusters have been systematically investigated using density functional theory (DFT) within the generalized gradient approximation (GGA). The result indicates that the ground state structures of WnH2 clusters are generated when H2 dissociative adsorbed on the atop site of Wn clusters. W8H2 and W[Formula: see text]H2 clusters are found to be more stable than other clusters. The adsorption abilities of Wn clusters are related to W–H bond length, adsorption energy and the charge transfer between H and W clusters as well as the electronic density of state.

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