Insights into the Adsorption of Water and Oxygen on the Cubic CsPbBr3 Surfaces: A First-Principle Study

2021 ◽  
Author(s):  
Xin Zhang ◽  
Ruge Quhe ◽  
Ming Lei
Keyword(s):  
Adsorption Energy ◽  
Density Functional ◽  
Degradation Mechanism ◽  
Perovskite Solar Cells ◽  
Density Functional Theory Calculations ◽  
Adsorbed Water ◽  
Energy Difference ◽  
Device Fabrication ◽  
Water Molecules ◽  
Inorganic Perovskite

Abstract The degradation mechanism of the all-inorganic perovskite solar cells in the ambient environment remains unclear. In this paper, water and oxygen molecule adsorptions on the all-inorganic perovskite (CsPbBr3) surface are studied by density-functional theory calculations. In terms of the adsorption energy, the water molecules are more susceptible than the oxygen molecules to be adsorbed on the CsPbBr3 surface. The water molecules can be adsorbed on both the CsBr- and PbBr-terminated surfaces, but the oxygen molecules tend to be selectively adsorbed on the CsBr-terminated surface instead of the PbBr-terminated one due to the significant adsorption energy difference. While the adsorbed water molecules only contribute deep states, the oxygen molecules introduce interfacial states inside the bandgap of the perovskite, which would significantly impact the chemical and transport properties of the perovskite. Therefore, special attention should be paid to reduce the oxygen concentration in the environment during the device fabrication process so as to improve the stability and performance of the CsPbBr3 based devices.

scholarly journals First-Principles Study of AlPO4-H3, a Hydrated Aluminophosphate Zeotype Containing Two Different Types of Adsorbed Water Molecules

Molecules ◽  
2019 ◽  
Vol 24 (5) ◽  
pp. 922 ◽  
Author(s):  
Michael Fischer
Keyword(s):  
Density Functional ◽  
Computational Study ◽  
Pore Space ◽  
Experimental Studies ◽  
Adsorbed Water ◽  
Working Fluid ◽  
Water Molecules ◽  
Small Pore ◽  
Experimental Crystal ◽  
Heat Transformation

Porous aluminophosphate zeotypes (AlPOs) are promising materials for heat transformation applications using water as a working fluid. Two “types” of adsorbed water molecules can be distinguished in hydrated AlPOs: Water molecules adsorbed in the direct proximity of framework aluminium atoms form bonds to these Al atoms, with the coordination number of Al increasing from four to five or six. The remaining water molecules that are adsorbed in other parts of the accessible pore space are not strongly bonded to any framework atom, they interact with their environment exclusively through hydrogen bonds. The APC-type small-pore aluminophosphate AlPO4-H3 contains both types of H2O molecules. In the present work, this prototypical hydrated AlPO is studied using dispersion-corrected density functional theory (DFT) calculations. After validating the computations against experimental crystal structure and Raman spectroscopy data, three interrelated aspects are addressed: First, calculations for various partially hydrated models are used to establish that such partially hydrated phases are not thermodynamically stable, as the interaction with the adsorbed water molecules is distinctly weaker than in fully hydrated AlPO4-H3. Second, IR and Raman spectra are computed and compared to those of the dehydrated analogue AlPO4-C, leading to the identification of a few “fingerprint” modes that could be used as indicators for the presence of Al-coordinated water molecules. Finally, DFT-based molecular dynamics calculations are employed to study the dynamics of the adsorbed water molecules. All in all, this in-depth computational study of AlPO4-H3 contributes to the fundamental understanding of hydrated AlPOs, and should therefore provide valuable information for future computational and experimental studies of these systems.

Insights into structural and dynamical features of water at halloysite interfaces probed by DFT and classical molecular dynamics simulations

2016 ◽  
Vol 18 (3) ◽  
pp. 2164-2174 ◽  
Author(s):  
Davide Presti ◽  
Alfonso Pedone ◽  
Giordano Mancini ◽  
Celia Duce ◽  
Maria Rosaria Tiné ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Water Molecules ◽  
Functional Theory ◽  
Structure And Dynamics ◽  
Classical Molecular Dynamics ◽  
Dynamical Features ◽  
Dynamics Simulations

Density functional theory calculations and classical molecular dynamics simulations have been used to investigate the structure and dynamics of water molecules on kaolinite surfaces and confined in the interlayer of a halloysite model of nanometric dimension.

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

2011 ◽  
Vol 233-235 ◽  
pp. 491-494 ◽  
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.

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

2011 ◽  
Vol 233-235 ◽  
pp. 495-498 ◽  
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.

Theoretical Insights into the Role of Water Molecule in The Aqueous/Cu(111) Interface during Corrosion Pathway

2014 ◽  
Vol 19 (4) ◽  
pp. 235-240
Author(s):  
Jun Hu ◽  
Xiao-yong Fan ◽  
Chao-Ming Wang
Keyword(s):  
Water Molecule ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Adsorbed Water ◽  
Dipole Interaction ◽  
Hydrogen Atoms ◽  
Functional Theory ◽  
Adsorbed Water Molecule ◽  
The One

The absorption and possible reaction paths during corrosion have been systematically identified at the molecular level by us-ing density functional theory calculations. The results show that the co-adsorbed water molecule has a two-fold impact on the corrosive kinetics process. The one is the solvation effect, where water molecule affects the various reactions through ion dipole interaction, without bond fracture and formation. Another is the H-transfer mediator, where the bond of co-adsorbed water molecule breaks and regenerates in order to transfer hydrogen atoms.

Improvement of the humidity stability of organic–inorganic perovskite solar cells using ultrathin Al2O3layers prepared by atomic layer deposition

2015 ◽  
Vol 3 (10) ◽  
pp. 5360-5367 ◽  
Author(s):  
Xu Dong ◽  
Xiang Fang ◽  
Minghang Lv ◽  
Bencai Lin ◽  
Shuai Zhang ◽  
...  
Keyword(s):  
Solar Cells ◽  
Atomic Layer Deposition ◽  
Perovskite Solar Cells ◽  
Atomic Layer ◽  
Water Molecules ◽  
Inorganic Perovskite ◽  
Layer Deposition ◽  
Negative Effect ◽  
High Polarity

The high polarity of water molecules inevitably causes the decomposition of perovskites. We retard the degradation by introducing an ultrathin ALD–Al2O3layer, which has almost no negative effect on performance.

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

2021 ◽  
Author(s):  
Sudarshan Vijay ◽  
Henrik Høgh Kristoffersen ◽  
Yu Katayama ◽  
Yang Shao-Horn ◽  
Ib Chorkendorff ◽  
...  
Keyword(s):  
Adsorption Energy ◽  
Density Functional ◽  
Configurational Entropy ◽  
Density Functional Theory Calculations ◽  
Temperature Programmed Desorption ◽  
Functional Theory ◽  
Interaction Terms ◽  
Saturation Coverage ◽  
Adsorption Energies ◽  
Temperature Programmed

<p>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 <i>steps</i> 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. <b></b></p>

scholarly journals Water dissociation and association on mirror twin boundaries in two-dimensional MoSe2: insights from density functional theory calculations

2021 ◽  
Author(s):  
Thomas Joseph ◽  
Mahdi Ghorbani-Asl ◽  
Matthias Batzill ◽  
Arkady V Krasheninnikov
Keyword(s):  
Density Functional Theory ◽  
Transition Metal ◽  
Point Defects ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Water Dissociation ◽  
Water Molecules ◽  
Two Dimensional ◽  
Functional Theory ◽  
Adsorption And Dissociation

The adsorption and dissociation of water molecules on two-dimensional transition metal dichalco- genides (TMDs) is expected to be dominated by point defects, such as vacancies, and edges. At the same...

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