Highest Ionic Conductivity of BIMEVOX (ME = 10% Cu, 10% Ga, 20% Ta): Computational Modeling and Simulation

BIMEVOX had the potential to play an important role in solid oxide fuel cell, especially as the electrolyte due to their high ionic conductivity. In this work, oxide ion migrations of γ-Bi2VO5.5 and BIMEVOX were simulated using density function theory (DFT), Mott-Littleton method, and molecular dynamic simulation. In γ-Bi2VO5.5, there were oxygen vacancies at the equatorial position in the vanadate layers. These vacancies could facilitate oxide ions migration. The Enthalpy of the oxide migration for γ-Bi2VO5.5 based on DFT calculation was 0.38 eV, which was in a good agreement with experimental results. The γ-Bi2VO5.5 can be stabilized by partial substitution of V5+ with Cu2+, Ga3+, and Ta5+. Defect simulation results using the Mott-Littleton method showed that the total maximum energies of region II were achieved at concentrations of 10, 10, and 20%, respectively for Cu2+, Ga3+, and Ta5+. The calculated concentration of Cu2+, Ga3+, and Ta5+ were in a good agreement with those of experiment results, where the highest ionic conductivity obtained. The results of the molecular dynamics simulation showed that the activation energies of oxide ion migration in γ-Bi2VO5.5 and BIMEVOX (ME = Cu and Ta) respectively were 0.19, 0.21, and 0.10 eV, close to experimental values.

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Ionic Conductivity, Structure and Oxide Ion Migration Pathway in Fluorite-Based Bi8La10O27

Chemistry of Materials ◽

10.1021/cm901770n ◽

2009 ◽

Vol 21 (19) ◽

pp. 4661-4668 ◽

Cited By ~ 14

Author(s):

Yuandi Li ◽

Tom P. Hutchinson ◽

Xiaojun Kuang ◽

Peter R. Slater ◽

Mark R. Johnson ◽

...

Keyword(s):

Ionic Conductivity ◽

Ion Migration ◽

Migration Pathway ◽

Conductivity Structure ◽

Oxide Ion

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Ionic Conductivity Study on the New High Oxide Conducting Perovskite LaGaO3

MRS Proceedings ◽

10.1557/proc-527-503 ◽

1998 ◽

Vol 527 ◽

Author(s):

G.V.M. Kiruthika ◽

U.V. Varadaraju

Keyword(s):

Activation Energy ◽

Ionic Conductivity ◽

Single Phase ◽

Ion Conductivity ◽

Lanthanum Gallate ◽

Migration Energy ◽

Ion Migration ◽

Oxide Ion Conductivity ◽

Unit Cell Size ◽

Oxide Ion

ABSTRACTOxide ion conductivity studies have been done on the Lanthanum Gallate based compounds. Yttrium substitution at the Ga site has been attempted to increase the unit cell size. Single phase was obtained for limited Y substituion i.e., La0.9Sr0.1Ga0.7Y0.1Mg0.2O3-x. It is found that the activation energy for the oxide ion conductivity has decreased for this composition. Based on the tolerance factor and B-site radius values, the migration energies were obtained for the LaGaO3 based perovskites. It is observed that migration energy has been significantly reduced upon substitution at the B-site. Absence of an enhancement in the conductivity with Yttrium substitution could be due to the vaccancy ordering inhibiting the oxide ion migration.

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ChemInform Abstract: Ionic Conductivity, Structure and Oxide Ion Migration Pathway in Fluorite-Based Bi8La10O27.

ChemInform ◽

10.1002/chin.201002019 ◽

2010 ◽

Vol 41 (2) ◽

Author(s):

Yuandi Li ◽

Tom P. Hutchinson ◽

Xiaojun Kuang ◽

Peter R. Slater ◽

Mark R. Johnson ◽

...

Keyword(s):

Ionic Conductivity ◽

Ion Migration ◽

Migration Pathway ◽

Conductivity Structure ◽

Oxide Ion

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Multicanonical Molecular Dynamics Simulation Study of the Liquid-Solid and Solid-Solid Transitions in Lennard-Jones Clusters

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44457 ◽

2011 ◽

Author(s):

Toshihiro Kaneko ◽

Kenji Yasuoka ◽

Ayori Mitsutake ◽

Xiao Cheng Zeng

Keyword(s):

Molecular Dynamics ◽

Heat Capacity ◽

Transition Temperature ◽

Peak Position ◽

Temperature Curve ◽

Dynamics Simulation ◽

Lennard Jones ◽

Dynamics Simulations ◽

First Time ◽

Good Agreement

Multicanonical molecular dynamics simulations are applied, for the first time, to study the liquid-solid and solid-solid transitions in Lennard-Jones (LJ) clusters. The transition temperatures are estimated based on the peak position in the heat capacity versus temperature curve. For LJ31, LJ58 and LJ98, our results on the solid-solid transition temperature are in good agreement with previous ones. For LJ309, the predicted liquid-solid transition temperature is also in agreement with previous result.

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Morphological effect of side chain on H3O+ transfer inside polymer electrolyte membranes across polymeric chain via molecular dynamics simulation

Scientific Reports ◽

10.1038/s41598-020-77971-6 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

JinHyeok Cha

Keyword(s):

Fuel Cell ◽

Ionic Conductivity ◽

Polymer Electrolyte ◽

Polymer Electrolyte Membrane ◽

Dynamics Simulation ◽

Polymeric Chain ◽

Side Chains ◽

Dynamic Simulations ◽

Morphological Effect ◽

Electrolyte Membrane

AbstractPerformance and durability of polymer electrolyte membrane are critical to fuel cell quality. As fuel cell vehicles become increasingly popular, membrane fundamentals must be understood in detail. Here, this study used molecular dynamic simulations to explore the morphological effects of perfluorosulfonic acid (PFSA)-based membranes on ionic conductivity. In particular, I developed an intuitive quantitative approach focusing principally on hydronium adsorbing to, and desorbing from, negatively charged sulfonate groups, while conventional ionic conductivity calculations featured the use of mean square displacements that included natural atomic vibrations. The results revealed that shorter side-chains caused more hydroniums to enter the conductive state, associated with higher ion conductivity. In addition, the hydronium path tracking showed that shorter side-chains allowed hydroniums to move among host groups, facilitating chain adsorption, in agreement with a mechanism suggested in earlier studies.

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Investigation of Microscopic Structure and Ion Dynamics in Liquid Li(Na, K)EutecticCl Systems by Molecular Dynamics Simulation

Applied Sciences ◽

10.3390/app8101874 ◽

2018 ◽

Vol 8 (10) ◽

pp. 1874 ◽

Cited By ~ 1

Author(s):

Jie Wu ◽

Jia Wang ◽

Haiou Ni ◽

Guimin Lu ◽

Jianguo Yu

Keyword(s):

Molecular Dynamics ◽

Ionic Conductivity ◽

Shear Viscosity ◽

Ion Pairs ◽

Liquid Structure ◽

Distribution Functions ◽

Dynamics Simulation ◽

Molten Chloride ◽

Ion Clusters ◽

Self Diffusion

Molten chloride salts are the main components in liquid metal batteries, high-temperature heat storage materials, heat transfer mediums, and metal electrolytes. In this paper, interest is centered on the influence of the LiCl component and temperature on the local structure and transport properties of the molten LiCl-NaCl-KCl system over the temperature range of 900 K to 1200 K. The liquid structure and properties have been studied across the full composition range by molecular dynamics (MD) simulation of a sufficient length to collect reliable values, such as the partial radial distribution function, angular distribution functions, coordination numbers distribution, density, self-diffusion coefficient, ionic conductivity, and shear viscosity. Densities obtained from simulations were underestimated by an average 5.7% of the experimental values. Shear viscosities and ionic conductivity were in good agreement with the experimental data. The association of all ion pairs (except for Li-Li and Cl-Cl) was weakened by an increasing LiCl concentration. Ion clusters were formed in liquids with increasing temperatures. The self-diffusion coefficients and ionic conductivity showed positive dependences on both LiCl concentration and temperature, however, the shear viscosity was the opposite. By analyzing the hydrodynamic radii of each ion and the coordination stability of cation-anion pairs, it was speculated that ion clusters could be the cation-anion coordinated structure and affected the macro properties.

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Electronic/Ionic Conductivity and Oxygen Diffusion Coefficient af the Sr-Fe-Co-O System

MRS Proceedings ◽

10.1557/proc-393-49 ◽

1995 ◽

Vol 393 ◽

Cited By ~ 18

Author(s):

B. Ma ◽

J.-H. Park ◽

C. U. Segre ◽

U. Balachandran

Keyword(s):

Diffusion Coefficient ◽

Ionic Conductivity ◽

Oxygen Diffusion ◽

Ionic Conductivities ◽

Transference Number ◽

Transference Numbers ◽

Oxygen Diffusion Coefficient ◽

Ionic Transference Number ◽

Local Fitting ◽

Oxide Ion

ABSTRACTOxides in the Sr-Fe-Co-O system exhibit both electronic and ionic conductivities. Recently, the Sr-Fe-Co-O system attracted great attention because of its potential to be used for oxygen-permeable membranes that can operate without electrodes or external electrical circuitry. Electronic and ionic conductivities of two compositions of the Sr-Fe-Co-O system, named SFC-1 and SFC-2, have been measured at various temperatures. The electronic transference number is much greater than the ionic transference number in SFC-1, whereas the electronic and ionic transference numbers are very similar in SFC-2. At 800°C, the electronic and ionic conductivities are ≈76 and ≈4 S•cm−1, respectively, for SFC-1; whereas, for SFC-2, the electronic and ionic conductivities are ≈10 and ∼1 S•cm−1, respectively. By performing a local fitting to the equation σ • T = Aexp(-Ea / kT), we found that the oxide ion activation energies are 0.92 and 0.37 eV, respectively, for SFC-1 and SFC-2. The oxygen diffusion coefficient of SFC-2 is ≈ 9 x 10−7cm2/sec at 900°C.

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MEASUREMENT OF SEDIMENT SUSPENSION IN COMBINATIONS OF WAVES AND CURRENTS

Coastal Engineering Proceedings ◽

10.9753/icce.v13.55 ◽

1972 ◽

Vol 1 (13) ◽

pp. 55

Author(s):

J. Kirkegarrd Jensen ◽

Torben Sorenson

Keyword(s):

Thin Layer ◽

Concentration Profile ◽

Field Data ◽

Concentration Profiles ◽

Sediment Suspension ◽

Calculated Concentration ◽

Waves And Currents ◽

The Mean ◽

Mean Concentration ◽

Good Agreement

The paper describes a procedure for obtaining field data on the mean concentration of sediments in combination of waves and currents outside the breaker zone, as well as some results of such measurements. It is assumed that the current turbulence alone is responsible for the maintenance of the concentration profile above a thin layer close to the bottom, in which pick-up of sediments due to wave agitation takes place. This assumption gives a good agreement between field data and calculated concentration profiles.

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GRANULAR MEDIA ON A VIBRATING PLATE: A MOLECULAR DYNAMICS SIMULATION

International Journal of Modern Physics B ◽

10.1142/s0217979293002572 ◽

1993 ◽

Vol 07 (09n10) ◽

pp. 1779-1788 ◽

Cited By ~ 5

Author(s):

JASON A.C. GALLAS ◽

HANS J. HERRMANN ◽

STEFAN SOKOLOWSKI

Keyword(s):

Molecular Dynamics ◽

Molecular Dynamics Simulation ◽

Granular Materials ◽

Granular Medium ◽

Granular Media ◽

Dynamics Simulation ◽

Dissipation Of Energy ◽

Conveyor Belts ◽

Good Agreement ◽

Vibrating Plate

When sand or other granular materials are shaken, poured or sheared many intriguing phenomena can be observed. We will model the granular medium by a packing of elastic spheres and simulate it via Molecular Dynamics. Dissipation of energy and shear friction at collisions are included. The onset of fluidization can be determined and is in good agreement with experiments. On a vibrating plate we observe the formation of convection cells due to walls or amplitude modulations. Density and velocity profiles on conveyor belts are measured and the influence of an obstacle discussed. We mention various types of rheology for flow down an inclined chute or through a pipe and outflowing containers.

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