How to Extract Adsorption Energies, Adsorbateadsorbate Interaction Parameters, and Saturation Coverages from Temperature Programmed Desorption Experiments

We present a simple scheme to extract the adsorption energy, adsorbate interaction parameter and the saturation coverage from temperature programmed desorption (TPD) experiments. We propose that the coverage dependent adsorption energy can be fit using a functional form including the configurational entropy and linear adsorbate-adsorbate interaction terms. As one example of this scheme, we analyze TPD spectra of desorption on Au(211) and Au(310) surfaces. We determine that under atmospheric pressure, the steps of both facets adsorb between 0.4-0.9 ML coverage of CO*. We show this result to be consistent with density functional theory calculations of adsorption energies with the BEEF-vdW functional.

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Elucidation of temperature-programmed desorption of high-coverage hydrogen on Pt(211), Pt(221), Pt(533) and Pt(553) based on density functional theory calculations

Physical Chemistry Chemical Physics ◽

10.1039/c9cp02330e ◽

2019 ◽

Vol 21 (31) ◽

pp. 17142-17151 ◽

Cited By ~ 2

Author(s):

Manuel J. Kolb ◽

Anna L. Garden ◽

Cansin Badan ◽

José A. Garrido Torres ◽

Egill Skúlason ◽

...

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Hydrogen Adsorption ◽

Density Functional Theory Calculations ◽

Temperature Programmed Desorption ◽

High Coverage ◽

Functional Theory ◽

Temperature Programmed

In this work, we compute high-coverage hydrogen adsorption structures on the Pt(211) and Pt(533) surfaces which contain a (100) step and the Pt(221) and Pt(553) surfaces which contain a (111) step and link these to their respective TPD spectra.

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Density Functional Theory Calculations of Arsenic(III) Structures on Perfect TiO2 Anatase (1 0 1) Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.233-235.491 ◽

2011 ◽

Vol 233-235 ◽

pp. 491-494 ◽

Cited By ~ 1

Author(s):

Lin Yu ◽

Yue Liu ◽

Zhi Gang Wei ◽

Gui Qiang Diao ◽

Ming Sun ◽

...

Keyword(s):

Density Functional Theory ◽

Adsorption Energy ◽

Density Functional ◽

Function Method ◽

Photocatalytic Oxidation ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Low Concentrations ◽

The Density Functional Theory ◽

The World

There are many areas in the world where the ground water has been contaminated by arsenic. One process to purify the water is to use TiO2 to adsorb the arsenic. As the TiO2 surface can be cleaned and reused, it has a promising potential as a water purifier. In this paper, the plane-wave function method, based on the density functional theory, has been used to calculate the structures of arsenic(III) on a perfect TiO2 anatase (1 0 1) surface. All the arsenic(III) solution species such as H3AsO3, H2AsO3-1, HAsO3-2 and AsO3-3 are put onto the surface with many different possible structures to obtain the adsorption energy. Based on the adsorption energy, the bidentate binuclear (BB) adsorption configurations of arsenic(III) on the surface are more favorable at low concentrations, whereas BB form and monodentate mononuclear (MM) form may coexist at higher concentrations. The models and results fit well with published experimental results. The results and conclusions will be of benefit to further research on arsenite adsorption and its photocatalytic oxidation on a TiO2 surface.

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Density Functional Theory Calculations of Arsenic(V) Structures on Perfect TiO2 Anatase (1 0 1) Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.233-235.495 ◽

2011 ◽

Vol 233-235 ◽

pp. 495-498 ◽

Cited By ~ 2

Author(s):

Zhi Gang Wei ◽

Yan Di Zou ◽

Hai Xia Zeng ◽

Xue Chun Zhong ◽

Zhen Jun Cheng ◽

...

Keyword(s):

Density Functional Theory ◽

Adsorption Energy ◽

Density Functional ◽

Function Method ◽

Photocatalytic Oxidation ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Low Concentrations ◽

The Density Functional Theory ◽

The World

There are many areas in the world where the ground water has been contaminated by arsenic. One process to purify the water is to use TiO2 to adsorb the arsenic. As the TiO2 surface can be cleaned and reused, it has a promising potential as a water purifier. In this paper, the plane-wave function method, based on the density functional theory, has been used to calculate the structures of arsenic(III) on a perfect TiO2 anatase (1 0 1) surface. All the arsenic(III) solution species such as H3AsO3, H2AsO3-1, HAsO3-2 and AsO3-3 are put onto the surface with many different possible structures to obtain the adsorption energy. Based on the adsorption energy, the bidentate binuclear (BB) adsorption configurations of arsenic(III) on the surface are more favorable at low concentrations, whereas BB form and monodentate mononuclear (MM) form may coexist at higher concentrations. The models and results fit well with published experimental results. The results and conclusions will be of benefit to further research on arsenite adsorption and its photocatalytic oxidation on a TiO2 surface.

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B(OH)2-functionalized graphene nanoflake as a promising nanocarrier for letrozole delivery: A DFT study

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/ac39c6 ◽

2021 ◽

Author(s):

Malakehsadat Seyedmousavi ◽

Morteza Rouhani ◽

Zohreh Mirjafary

Keyword(s):

Adsorption Energy ◽

Density Functional ◽

Anticancer Agent ◽

Density Functional Theory Calculations ◽

Pristine Graphene ◽

Physical Interaction ◽

Functionalized Graphene ◽

Functional Theory ◽

Graphene Nanoflakes ◽

Graphene Nanoflake

Abstract We studied the capability of pristine, Al-doped and B(OH)2-functionalized graphene nanoflakes for delivery of Letrozole (LT) anticancer agent using density functional theory calculations. It was shown that LT/pristine graphene complex includes very weak physical interaction with Ead = -2.447 kcal.mol-1 which is so weak to be applied in drug delivery purposes. So, graphene nanoflake was doped by Al atom and the calculations demonstrated the LT adsorption energy was increased significantly (Ead = -33.571 kcal.mol-1). However, the LT release study showed that the adsorption energy did not change efficiently upon protonation in acidic environment (Ead = -31.857 kcal.mol-1). Finally, the LT adsorption was investigated on B(OH)2-functionalized graphene. The calculations represented that the adsorption energy was -9.607 kcal.mol-1 which can be attributed to the possible hydrogen bonding between LT molecule and B(OH)2 functional group. The adsorption energy was changed to -1.015 kcal.mol-1 during protonation process. It can be concluded that the protonation of LT/B(OH)2-functionalized graphene complex in carcinogenic cells area, separates the LT from the nanocarrier. Thus, B(OH)2-functionalized graphene nanoflakes can be considered as a promising nanocarrier candidate for LT delivery.

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Precursor chemistry of h-BN: adsorption, desorption, and decomposition of borazine on Pt(110)

Physical Chemistry Chemical Physics ◽

10.1039/d0cp00112k ◽

2020 ◽

Vol 22 (20) ◽

pp. 11704-11712 ◽

Cited By ~ 1

Author(s):

Leander Haug ◽

Jannik P. Roth ◽

Marco Thaler ◽

Dominik Steiner ◽

Alexander Menzel ◽

...

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Precursor Chemistry ◽

Temperature Programmed Desorption ◽

Photoemission Spectroscopy ◽

Functional Theory ◽

P Adsorption ◽

Ultraviolet Photoemission Spectroscopy ◽

Temperature Programmed ◽

Adsorption Desorption

Adsorption, desorption and fragmentation of borazine on Pt(110) are studied by temperature-programmed desorption, ultraviolet photoemission spectroscopy, workfunction measurements and density functional theory.

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Molecular Oxygen Adsorbed on Gallium Doped Graphene: A First-Principles Study

Materials Science Forum ◽

10.4028/www.scientific.net/msf.890.117 ◽

2017 ◽

Vol 890 ◽

pp. 117-120

Author(s):

Seba Sara Varghese ◽

Sundaram Swaminathan ◽

Krishna Kumar Singh ◽

Vikas Mittal

Keyword(s):

Electronic Properties ◽

Molecular Oxygen ◽

Adsorption Energy ◽

First Principles ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Strong Interactions ◽

Functional Theory ◽

Before And After ◽

Doped Graphene

The adsorption of molecular oxygen on gallium doped graphene sheet is investigated using first-principles density functional theory calculations. The adsorption energy of O2 on gallium doped graphene is calculated after determining the energetically favourable adsorption configuration. The change in the electronic properties of gallium doped graphene after O2 adsorption is also determined to understand the nature their interactions. The results show that gallium doped graphene has large adsorption energy and small binding distance, which correspond to chemical adsorption. The calculated band structure and density of states plots of gallium doped graphene before and after adsorption show dramatic changes in the electronic properties due to the strong interactions of gallium doped graphene with adsorbed O2 molecule. These results indicate that gallium doped graphene is highly reactive to molecular oxygen and hence not a suitable choice for harmful gas detection in the presence of O2.

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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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Composition and Dimension Dependent Static and Dynamic Stabilities of Inorganic Mixed Halide Antimony Perovskites

10.26434/chemrxiv.14191301.v1 ◽

2021 ◽

Author(s):

Jack Yang

Keyword(s):

Density Functional ◽

Configurational Entropy ◽

Density Functional Theory Calculations ◽

Optoelectronic Properties ◽

Lead Free ◽

Photovoltaic Devices ◽

Functional Theory ◽

Inorganic Lead ◽

Electronic Dynamics ◽

Important Approach

Halide intermixing is an important approach to stabilise halide perovskite in the phase that gives the best optoelectronic properties, whereas replacing Pb is critical for eliminating the material toxicity to meet the requirements for domestic applications. Recently, all-inorganic lead-free Cs3Sb2I9 emerges as a promising lead-free absorber, with its optoelectronic properties being further controllable by manipulating its structural dimensionality (0D or 2D) via composition engineering. In particular, superior photoconversion efficiency (up to 5 %) under indoor illumination with high photostabilities have been demonstrated experimentally in 2D Cs3Sb2ClyI9-y}. To gain a more thorough understanding on how the properties of this family of materials are controlled by their chemistry and dimensionality, here, we employ density functional theory calculations to explore the phase stability, structural and electronic dynamics of Cs3Sb2X9 (X=Br and Cl) across 74 different combinations of composition/dimensionality. The results show that Cs3Sb2X9 solid solutions are predominantly stabilised by configurational entropy rather than enthalpy. In stark contrast to cubic inorganic lead/tin halides perovskites, Cs3Sb2X9 are dynamically more stable at 300 K, as reflected by their low vibrational anharmonicities, the values of which also exhibit weak compositional dependency. This consequentially reduces the strength of electron-phonon couplings, thus enhancing the photoexcited carrier lifetime in these materials, which further demonstrates their promising potential to be integrated into indoor photovoltaic devices.

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DENSITY FUNCTIONAL THEORY STUDIES ON THE ADSORPTION OF 4-METHYLBENZENETHIOL AND 4-ETHYLBENZENETHIOL MOLECULES ON Au(111) SURFACE

Surface Review and Letters ◽

10.1142/s0218625x14500875 ◽

2014 ◽

Vol 21 (06) ◽

pp. 1450087 ◽

Cited By ~ 1

Author(s):

XIAOLIANG FANG ◽

XIAOLI FAN ◽

RUNXIN RAN ◽

PIN XIAO

Keyword(s):

Density Functional Theory ◽

Tilt Angle ◽

Adsorption Energy ◽

First Principles ◽

Density Functional ◽

Energy Calculation ◽

Functional Theory ◽

Calculation Results ◽

Adsorption Energies ◽

First Principles Method

The nondissociative and dissociated adsorptions of 4-methylbenzenethiol (4-MBT) and 4-ethylbenzenethiol (4-EBT) on Au (111) surface were studied by applying the first-principles method based on density functional theory. The effects of coverage and vdW interactions on adsorptions were investigated. Adsorption energies and tilt angles of both 4-MBT and 4-EBT decrease with the increase of the coverage, and vdW interactions can affect the adsorption configuration and energy. More importantly, in the case of 4-EBT adsorption, we have studied the effects of ethyl group's orientation on the adsorption configuration and energy. Calculation results show that ethyl group's orientation has little effect on the adsorption energy, but changes the tilt angle by around 7°. Our calculations provide a deeper elucidation of the observed adsorption configuration for 4-EBT on Au (111).

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