Hydrogen Diffusion and Adsorption on WO3 (001) based on First Principles Calculation

Hydrogen reduction of tungsten oxide is currently the most widely applied ultrafine tungsten powder production process. The process has the advantage of short, pollution free and simple production equipment. But it is difficult to effectively control the morphology and particle size of the tungsten powder because of lacking in-depth understanding of the dynamic mechanism of the process. The first-principles calculations are carried out to explore the diffusion and internal adsorption of hydrogen on the WO-terminated surface of WO3 based on the density functional theory. The results show that hydrogen can diffuse from the WO terminal surface to the inside of WO3, the activation energy of diffusion is 46.682 Kcal/mol. It’s preferable for hydrogen to diffuse from the surface to the inside than diffuse within the WO3 lattice. The adsorption energy of hydrogen on the WO termination surface of WO3 is 15.093 Kcal/mol, the adsorption energy of hydrogen inside the WO termination surface of WO3 is 14.116 Kcal/mol, which means the hydrogen is easier to adsorb inside the WO3 lattice.

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Hydrogen Atom Adsorption on α-Al2O3(0001) Surface from First Principles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.2261 ◽

2011 ◽

Vol 399-401 ◽

pp. 2261-2265 ◽

Cited By ~ 2

Author(s):

Jian Gong Hu ◽

Yi Sheng Zhang ◽

Li Chao Jia ◽

Bin Zhu ◽

Hong Guang Yang ◽

...

Keyword(s):

Adsorption Energy ◽

First Principles ◽

Density Functional ◽

First Principles Calculation ◽

Large Decrease ◽

Generalized Gradient ◽

Functional Theory ◽

Generalized Gradient Approximation ◽

The Density Functional Theory ◽

Low Coverage

First-principles calculation based on the density functional theory in the generalized gradient approximation was adopted to systematically investigate the α-Al2O3(0001) surface structure and the adsorption of H atom on the α-Al2O3(0001) surface. The calculations show that the O atop site is the energetically most favorable adsorption site at low coverage: at the H coverage of 1/6 ML (monolayer), the adsorption energy reaches up to7.61eV; in the regime of higher H coverages, the H atoms prefer to form atom cluster on the α-Al2O3(0001) surface, and the adsorption energy on the α-Al2O3(0001) with a pre-adsorbed H atom gets smaller, which illustrates that α-Al2O3that can prevent the penetration of hydrogen. With the increase of H coverage, the dipole moment reduces, which leads to a large decrease in the work function.

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First principles study of the adsorption and dissociation mechanisms of H2S on a TiO2anatase (001) surface

RSC Advances ◽

10.1039/c5ra20875k ◽

2016 ◽

Vol 6 (10) ◽

pp. 7941-7949 ◽

Cited By ~ 9

Author(s):

Naeem Shahzad ◽

Akhtar Hussain ◽

Naeem Mustafa ◽

Nisar Ali ◽

Mohammed Benali Kanoun ◽

...

Keyword(s):

Density Functional Theory ◽

First Principles ◽

Density Functional ◽

First Principles Calculation ◽

Functional Theory ◽

P Adsorption ◽

First Principles Study ◽

The Density Functional Theory ◽

Dissociation Mechanisms ◽

Adsorption And Dissociation

Adsorption and dissociation mechanisms of H2S on a TiO2(001) surface were elucidated using first principles calculation based on the density functional theory.

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First Principles Study of Gas Molecules Adsorption on Monolayered β-SnSe

Coatings ◽

10.3390/coatings9060390 ◽

2019 ◽

Vol 9 (6) ◽

pp. 390 ◽

Cited By ~ 1

Author(s):

Tianhan Liu ◽

Hongbo Qin ◽

Daoguo Yang ◽

Guoqi Zhang

Keyword(s):

Gas Sensors ◽

Adsorption Energy ◽

First Principles ◽

Density Functional ◽

Adsorption Properties ◽

First Principles Calculation ◽

Functional Theory ◽

Β Phase ◽

Physical Sensor ◽

Gas Molecules

For the purpose of exploring the application of two-dimensional (2D) material in the field of gas sensors, the adsorption properties of gas molecules, CO, CO2, CH2O, O2, NO2, and SO2 on the surface of monolayered tin selenium in β phase (β-SnSe) has been researched by first principles calculation based on density functional theory (DFT). The results indicate that β-SnSe sheet presents weak physisorption for CO and CO2 molecules with small adsorption energy and charge transfers, which show that a β-SnSe sheet is not suitable for sensing CO and CO2. The adsorption behavior of CH2O molecules adsorbed on a β-SnSe monolayer is stronger than that of CO and CO2, revealing that the β-SnSe layer can be applied to detect CH2O as physical sensor. Additionally, O2, NO2, and SO2 are chemically adsorbed on a β-SnSe monolayer with moderate adsorption energy and considerable charge transfers. All related calculations reveal that β-SnSe has a potential application in detecting and catalyzing O2, NO2, and SO2 molecules.

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First Principles Calculation on Adsorption of S on Fe(100) with Different Pressure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.217-219.1811 ◽

2012 ◽

Vol 217-219 ◽

pp. 1811-1814

Author(s):

Xue Tao Hu ◽

Qiang Luo ◽

Zeng Ling Ran

Keyword(s):

Hydrostatic Pressure ◽

Adsorption Energy ◽

First Principles ◽

Density Functional ◽

First Principles Calculation ◽

Hollow Site ◽

Generalized Gradient ◽

Functional Theory ◽

Generalized Gradient Approximation ◽

Adsorption Energies

Using periodic density functional theory within the generalized-gradient approximation to electron exchange and correlation, we have studied S adsorption four-fold hollow site on Fe(100) in different hydrostatic pressure. We find that the adsorption height decreases with hydrostatic pressure increasing is non-monotonic. The adsorption energy decreases with an increase with pressure is monotonic and we have obtained density of states is almost unchanged, the adsorption energy change is mainly caused by lattice deformation in the hydrostatic pressure, and the adsorption energies increase linearly with pressure.

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First-principles study of Li decorated coronene graphene

International Journal of Modern Physics B ◽

10.1142/s0217979217502162 ◽

2017 ◽

Vol 31 (29) ◽

pp. 1750216

Author(s):

Yafei zhang ◽

Xinlu Cheng

Keyword(s):

Density Functional Theory ◽

Hydrogen Storage ◽

Adsorption Energy ◽

First Principles ◽

Density Functional ◽

Department Of Energy ◽

First Principles Calculation ◽

Hydrogen Storage Materials ◽

Functional Theory ◽

The Us

We use the first-principles calculation based on density functional theory (DFT) to investigate the hydrogen storage of Li decorated coronene graphene. Our result indicates that single Li atom can adsorb three H2 molecules and the adsorption energy per H2 is −0.224 eV. When four Li atoms doped, the largest hydrogen gravimetric density is 6.82 wt.% and this is higher than the 2017 target by the US department of energy (DOE). Meanwhile, the adsorption energy per H2 is −0.220 eV, which is suitable for H2 molecules to store. Therefore, Li decorated coronene graphene will be a candidate for hydrogen storage materials in the future.

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First-Principles Studies on the Component Dependences of High-Entropy Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.338.380 ◽

2011 ◽

Vol 338 ◽

pp. 380-383 ◽

Cited By ~ 8

Author(s):

Shao Qing Wang ◽

Heng Qiang Ye

Keyword(s):

First Principles ◽

Density Functional ◽

Lattice Structure ◽

First Principles Calculation ◽

High Entropy Alloys ◽

Functional Theory ◽

High Entropy ◽

Composition Variation ◽

The Density Functional Theory

An elabrate study on the structrural and mechanical properties of the five-element FeNiCrCuCo high-entropy alloys is carried out by first-principles calculation within the density-functional theory. The combination application of plane-wave pseudopotentials and alchemical pseudoatom methods is realized to imitate the random elemental lattice occupation in the alloys. The dependence of composition variation to the crystallographic and thermodynamic properties of FeNiCrCuCo alloys in simple BCC and FCC lattices are investigated. The key role of chromium in strengthening the inter-atomic cohesion and stabilizing the lattice structure of HEAs is suggested.

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First-Principles Calculation of Defect Formation and Positron Annihilation States in Bi2Te3

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.373.41 ◽

2017 ◽

Vol 373 ◽

pp. 41-45 ◽

Cited By ~ 2

Author(s):

Bin Zhao ◽

Bo Zhou ◽

Chong Yang Li ◽

Ning Qi ◽

Zhi Quan Chen

Keyword(s):

First Principles ◽

Density Functional ◽

Formation Energy ◽

Defect Formation ◽

First Principles Calculation ◽

Functional Theory ◽

Rich Condition ◽

The Density Functional Theory ◽

Positron Wave Function ◽

Positron Lifetimes

Defect formation energy in Bi2Te3 thermoelectric material was calculated using a first principles approach based on the Density Functional Theory (DFT). For vacancy-type defect, the Te1 vacancy (VTe1) is the most stable defect with low formation energy in both Bi-rich and Te-rich conditions, which indicates that the Te1 vacancies have higher probability to be formed. For antisite defects, the formation energy of BiTe1 is much lower than that of BiTe2 in Bi-rich condition, while in Te-rich condition it is beneficial for TeBi with lower formation energy. Positron wave function distribution and positron lifetimes of different annihilation states in Bi2Te3 were also calculated using the atomic superposition (ATSUP) method. The positron bulk lifetime in Bi2Te3 is about 231 ps, and for the neutral vacancy-type defects without relaxation, the positron lifetimes of VBi, VTe1 and VTe2 are 275 ps, 295 ps and 269 ps, respectively.

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First Principles Calculation on Adsorption of S on Fe(111)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.704.120 ◽

2013 ◽

Vol 704 ◽

pp. 120-125

Author(s):

Feng Chun Zhang ◽

Chun Fu Li ◽

Zeng Ling Ran

Keyword(s):

Density Functional Theory ◽

Sulfur Atom ◽

Adsorption Energy ◽

First Principles ◽

Density Functional ◽

Density Functional Theory Calculations ◽

First Principles Calculation ◽

Hollow Site ◽

Functional Theory ◽

State Charge

Density functional theory calculations have been performed for sulfur atom adsorption on the Fe(111) surface at 0.5 and 1.0 ML. The geometry structures, density of the state, charge population and adsorption energy were calculated. It is found that the most favored adsorption site for sulfur atom is the hollow site, and the interaction between Fe and S comes in large part from the hybridization of Fe 3d orbital and S 3p orbital. Our results have shown that the force between iron atom and sulfur atom is very small.

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Electron-phonon interaction in In-induced √7 ×√3 structures on Si(111) from first-principles

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05234e ◽

2021 ◽

Author(s):

I. Yu. Sklyadneva ◽

Rolf Heid ◽

Pedro Miguel Echenique ◽

Evgueni Chulkov

Keyword(s):

Density Functional Theory ◽

Double Layer ◽

First Principles ◽

Linear Response ◽

Density Functional ◽

Single Layer ◽

Phonon Interaction ◽

Functional Theory ◽

Electron Phonon Interaction ◽

The Density Functional Theory

Electron-phonon interaction in the Si(111)-supported rectangular √(7 ) ×√3 phases of In is investigated within the density-functional theory and linear-response. For both single-layer and double-layer √(7 ) ×√3 structures, it...

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Electronic structure of the thermoelectric materials PbTe and AgPb18SbTe20 from first-principles calculations

Journal of Materials Research ◽

10.1557/jmr.2010.0145 ◽

2010 ◽

Vol 25 (6) ◽

pp. 1030-1036 ◽

Cited By ~ 4

Author(s):

Pengxian Lu ◽

Zigang Shen ◽

Xing Hu

Keyword(s):

Band Structure ◽

Thermoelectric Properties ◽

First Principles ◽

Electronic Structures ◽

Density Functional ◽

Partial Density ◽

Functional Theory ◽

The Density Functional Theory ◽

Scanning Transmission ◽

Linearized Augmented Plane Wave

To investigate the effects of substituting Ag and Sb for Pb on the thermoelectric properties of PbTe, the electronic structures of PbTe and AgPb18SbTe20 were calculated by using the linearized augmented plane wave based on the density-functional theory of the first principles. By comparing the differences in the band structure, the partial density of states (PDOS), the scanning transmission microscope, and the electron density difference for PbTe and AgPb18SbTe20, we explained the reason from the aspect of electronic structures why the thermoelectric properties of AgPb18SbTe20 could be improved significantly. Our results suggest that the excellent thermoelectric properties of AgPb18SbTe20 should be attributed in part to the narrowing of its band gap, band structure anisotropy, the much extrema and large DOS near Fermi energy, as well as the large effective mass of electrons. Moreover, the complex bonding behaviors for which the strong bonds and the weak bonds are coexisted, and the electrovalence and covalence of Pb–Te bond are mixed should also play an important role in the enhancement of the thermoelectric properties of the AgPb18SbTe20.

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