Mechanistic insight into oxygen vacancy migration in SrFeO3–δ from DFT+U simulations

2021 ◽  
Author(s):  
Musa Alaydrus ◽  
Ikutaro Hamada ◽  
Yoshitada Morikawa
Keyword(s):  
Oxygen Vacancy ◽  
Oxygen Reduction ◽  
Oxygen Vacancies ◽  
Structural Transitions ◽  
Ion Conductor ◽  
Vacancy Migration ◽  
Oxygen Ion ◽  
Mechanistic Insight ◽  
Oxygen Ion Conductor ◽  
Insight Into

SrFeO3–δ is known to be an effective oxygen ion conductor and oxygen vacancies are central to its performance. SrFeO3–δ displays four crystallographic structural transitions as it undergoes oxygen reduction over...

Evidence for the dynamic relaxation behavior of oxygen vacancies in Aurivillius Bi2MoO6 from dielectric spectroscopy during resistance switching

2019 ◽  
Vol 7 (29) ◽  
pp. 8915-8922 ◽  
Author(s):  
Fei Guo ◽  
Mengting Zhao ◽  
Kang Xu ◽  
Yu Huan ◽  
Shuaipeng Ge ◽  
...  
Keyword(s):  
Resistive Switching ◽  
Dielectric Spectroscopy ◽  
Oxygen Vacancies ◽  
Relaxation Behavior ◽  
Switching Behavior ◽  
Dynamic Relaxation ◽  
Resistive Switching Behavior ◽  
Ion Conductor ◽  
Oxygen Ion ◽  
Oxygen Ion Conductor

The resistive switching behavior of oxygen ion conductor Bi2MoO6 were investigated by dielectric spectroscopy.

Rationalization on high-loading iron and cobalt dual metal single atoms and mechanistic insight into the oxygen reduction reaction

Nano Energy ◽  
2022 ◽  
Vol 93 ◽  
pp. 106793
Author(s):  
Min Jiang ◽  
Fei Wang ◽  
Fan Yang ◽  
Hao He ◽  
Jian Yang ◽  
...  
Keyword(s):  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Reduction Reaction ◽  
High Loading ◽  
Single Atoms ◽  
Mechanistic Insight ◽  
Dual Metal ◽  
Insight Into

Oxygen vacancy migration in CSZ using density functional theory

2008 ◽  
Vol 1122 ◽  
Author(s):  
Byeong-Eon Lee ◽  
Dae-Hee Kim ◽  
Yeong-Cheol Kim
Keyword(s):  
Density Functional Theory ◽  
Oxygen Vacancy ◽  
Density Functional ◽  
Oxygen Vacancies ◽  
Nearest Neighbor ◽  
Functional Theory ◽  
The Third ◽  
Vacancy Migration ◽  
Neighbor Site ◽  
Formation Energies

AbstractWe studied oxygen migration in calcia-stabilized cubic zirconia (CSZ) using density functional theory. A Ca atom was substituted for a Zr atom in a 2×2×2 ZrO2 cubic supercell, and an oxygen vacancy was produced to satisfy the charge neutrality condition. We found that the formation energies of an oxygen vacancy, as a function of its location with respect to the Ca atom, were varied. The relative formation energies of the oxygen vacancies located at the first-, second-, third-, and fourth-nearest-neighbors were 0.0, −0.07, 0.19, and 0.19 eV, respectively. Therefore, the oxygen vacancy located at the second-nearest-neighbor site of the Ca atom was the most favorable, the oxygen vacancy located at the first-nearest-neighbor site was the second most favorable, and the oxygen vacancies at the third- and fourth-nearest-neighbor sites were the least favorable. We also calculated the energy barriers for the oxygen vacancy migration between oxygen sites. The energy barriers between the first and the second nearest sites, the second and third nearest sites, and the third and fourth nearest sites were 0.11, 0.46, and 0.23 eV, respectively. Therefore, the oxygen vacancies favored the first- and second-nearest-neighbor oxygen sites when they drifted under an electric field.

THERMODYNAMICS AND CATION DIFFUSION IN THE OXYGEN ION CONDUCTOR LSGM

2004 ◽  
pp. 787-797 ◽  
Author(s):  
M. MARTIN ◽  
O. SCHULZ
Keyword(s):  
Cation Diffusion ◽  
Ion Conductor ◽  
Oxygen Ion ◽  
Oxygen Ion Conductor

Microstructure and Property Study of La2Mo1.5W0.5O9/Ag Composites

2010 ◽  
Vol 663-665 ◽  
pp. 620-624
Author(s):  
Chun Li ◽  
Da Li ◽  
Qian Feng Fang
Keyword(s):  
Solid State Reaction Method ◽  
Second Phase ◽  
Doping Amount ◽  
Conventional Solid State Reaction ◽  
Single Phase Sample ◽  
Ion Conductor ◽  
Oxygen Ion ◽  
Direct Current Conductivity ◽  
Oxygen Ion Conductor ◽  
Sample Density

Based on the oxygen ion conductor La2Mo1.5W0.5O9, a series of Ag2O doped samples La2Mo1.5W0.5O9/Ag were prepared with conventional solid-state reaction method. The effects of Ag2O doping on the microstructure and electrical conductivity have been investigated by XRD, FESEM and direct current conductivity measurements. With the increase of Ag2O doping, the grain was further refined and compacted, meanwhile, Ag diffusion distribution in the form of second-phase appear at grain boundary. The sample density and conductivity also gradually increased with the increasing of doping amount. The conductivity of the composite specimen La2Mo1.5W0.5O9 /Ag has a great enhancement when the concentration of Ag2O is around 27 wt%, which is eight times higher than that of the single-phase sample.

Electrical properties of ultrafine-grained yttria-stabilized zirconia ceramics

1997 ◽  
Vol 12 (9) ◽  
pp. 2374-2380 ◽  
Author(s):  
Shusheng Jiang ◽  
Walter A. Schulze ◽  
Vasantha R. W. Amarakoon ◽  
Gregory C. Stangle
Keyword(s):  
Grain Size ◽  
Oxygen Vacancy ◽  
Grain Boundary ◽  
Oxygen Vacancies ◽  
Synthesis Process ◽  
Physical Parameters ◽  
Fine Grained ◽  
Oxygen Ion ◽  
Average Grain Size ◽  
Vacancy Concentrations

Nanoparticles of yttria-doped tetragonal zirconia polycrystalline ceramics (Y-TZP) with an average crystallite size of less than 9 nm were prepared by a combustion synthesis process. Dense and fine-grained (<200 nm) Y-TZP ceramics were obtained by fast-firing using temperatures lower than 1400 °C and dwell times of less than 2 min. Impedance spectroscopy was employed to measure conductivities of oxygen vacancies in the grain and the grain boundary of the fine-grained Y-TZP. The relationships between the concentration of the oxygen vacancies in the grain boundary and measurable physical parameters were determined semiquantitatively. The oxygen vacancy concentrations and activation energies for the oxygen-ion conduction in the grain and the grain boundary of the fine-grained Y-TZP were found to be independent of the average grain size in the average grain-size range of 90–200 nm. These experimental results suggest that, in order to retain the abnormally high oxygen vacancy concentrations of the Y-TZP nanoparticles and thus enhance the oxygen-ion conductivity, it may be necessary to decrease the average grain size to approximately 10 nm.

Activity of Bi2O3 in Bi2O3Y2O3 oxygen ion conductor

1992 ◽  
Vol 98 (1) ◽  
pp. 206-209 ◽  
Author(s):  
Keqin Huang ◽  
Changzhen Wang ◽  
Xiuguang Xu
Keyword(s):  
Ion Conductor ◽  
Oxygen Ion ◽  
Oxygen Ion Conductor
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