Anisotropic O vacancy formation and diffusion in LaMnO3

2014 ◽  
Vol 2 (46) ◽  
pp. 19733-19737 ◽  
Author(s):  
Li-Yong Gan ◽  
Salawu Omotayo Akande ◽  
Udo Schwingenschlögl
Keyword(s):  
Vacancy Formation ◽  
O Vacancy ◽  
And Diffusion

Preferential location of zirconium dopants in cerium dioxide nanoparticles and the effects of doping on their reducibility: a DFT study

2020 ◽  
Vol 22 (45) ◽  
pp. 26568-26582
Author(s):  
Iskra Z. Koleva ◽  
Hristiyan A. Aleksandrov ◽  
Konstantin M. Neyman ◽  
Georgi N. Vayssilov
Keyword(s):  
Cerium Dioxide ◽  
Dft Study ◽  
Vacancy Formation ◽  
Ceria Nanoparticles ◽  
Zirconium Doping ◽  
Mixed Nanoparticles ◽  
O Vacancy ◽  
Preferential Location

Zirconium doping dramatically facilitates O vacancy formation in ceria nanoparticles not only at the surface but also in four-coordinated inner O positions, which enhances O mobility. In mixed nanoparticles zirconium tends to occupy inner sites.

Ab Initio Studies of Nb Doping Effect on the Formation and Diffusion of Oxygen Vacancy and Ti Interstitial in Rutile TiO2

2011 ◽  
Vol 304 ◽  
pp. 142-147 ◽  
Author(s):  
Xu Wang ◽  
Fu He Wang
Keyword(s):  
Activation Energy ◽  
Oxygen Vacancy ◽  
Density Functional Calculations ◽  
Density Functional ◽  
Formation Energy ◽  
Suppressive Effect ◽  
Nb Doping ◽  
O Vacancy ◽  
And Migration ◽  
And Diffusion

The effect of Nb doping on the formation and diffusion of O vacancies and interstitial Ti in rutile TiO2 are studied by the use of ab initio density-functional calculations. Our calculation showed that the activation energy for the diffusion of O vacancy with Nb doping is higher than that of pure. That owing to suppressive effect of Nb doping on the formation of O vacancy. Different from the effect of Nb doping on O vacancy, both of the formation energy and migration barrier of interstitial Ti increase with the Nb doping. Our calculated results may be one of the reasons why Nb doping can improve oxidation resistance of γ-TiAl.

Thermodynamics of Oxygen Chemistry on PbTiO3 and LaMnO3 (001) Surfaces

2011 ◽  
Vol 1309 ◽  
Author(s):  
Ghanshyam Pilania ◽  
R. Ramprasad
Keyword(s):  
Phase Diagram ◽  
High Temperatures ◽  
First Principles ◽  
Room Temperature ◽  
Oxidation Catalysis ◽  
Vacancy Formation ◽  
Surface Phase ◽  
Surface Phases ◽  
O Vacancy ◽  
Low Pressures

ABSTRACTWe present a first principles thermodynamic study of O ad-atom and vacancy formation on the AO- and BO2-terminated (001) surfaces of the PbTiO3 (PTO) and LaMnO3 (LMO) cubic perovskites. Our results show that, owing to the highly energetically unfavorable nature of O vacancy formation on these surfaces, O vacancies appear only at high temperatures and practically irrelevant low pressures on the (T, p) surface phase diagram. In contrast, effortless formation of O ad-atoms on the surfaces is encountered at practically achievable pressures and temperatures. Above room temperature and close to atmospheric pressures, we predict clean PbO and TiO2-terminated (001) PTO surfaces as the stable surface phases while partially or fully O ad-atom covered surfaces are found to be more stable for LMO. These results are consistent with the observation that LMO is far more active towards oxidation catalysis than PTO.

Functionalization of CeO2(1 1 1) by Deposition of Small Ni Clusters: Effects on CO2Adsorption and O Vacancy Formation

ChemCatChem ◽  
2015 ◽  
Vol 7 (4) ◽  
pp. 625-634 ◽  
Author(s):  
Konstanze R. Hahn ◽  
Ari P. Seitsonen ◽  
Marcella Iannuzzi ◽  
Jürg Hutter
Keyword(s):  
Vacancy Formation ◽  
O Vacancy ◽  
Ni Clusters

scholarly journals The impact of oxygen vacancies on lithium vacancy formation and diffusion in Li2-MnO3-

2016 ◽  
Vol 289 ◽  
pp. 87-94 ◽  
Author(s):  
Christine James ◽  
Yan Wu ◽  
Brian W. Sheldon ◽  
Yue Qi
Keyword(s):  
Oxygen Vacancies ◽  
Vacancy Formation ◽  
The Impact ◽  
And Diffusion ◽  
Lithium Vacancy
Sign in / Sign up

Export Citation Format

Share Document