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Evidence for subsurface ordering of oxygen vacancies on the reduced CeO2 (111) surface using density-functional and statistical calculations
(American Physical Society, 2013-06)
Oxygen vacancies on ceria (CeO2) surfaces play a crucial role in catalytic applications, yet whether vacancies are at surface or subsurface sites on reduced CeO2 (111) , and whether vacancies agglomerate or repel each ...
Ordering of oxygen vacancies and excess charge localization in bulk ceria: A DFT+U study
(American Physical Society, 2014-09)
The importance of ceria (CeO2) in many applications originates from the ease of oxygen vacancy formation and healing. The ordering of vacancies and the whereabouts of the excess charge in bulk CeO2 are of no less significance ...
Oxygen vacancies dynamics in redox-based interfaces: Tailoring the memristive response
(IOP Publishing, 2019-09)
Redox-based memristive devices are among the alternatives for the next generation of non-volatile memories, but also candidates to emulate the behavior of synapses in neuromorphic computing de- vices. Nowadays it is well ...
Relative Stability of Near-Surface Oxygen Vacancies at the CeO2(111) Surface upon Zirconium Doping
(American Chemical Society, 2019-12)
The effects of Zr doping on the stability of the CeO2(111) surface as a function of the dopant concentration and distribution, as well as on the relative stability of surface and subsurface oxygen vacancies, were studied ...
Coupling of Acetaldehyde to Crotonaldehyde on CeO 2-x (111): Bifunctional Mechanism and Role of Oxygen Vacancies
(American Chemical Society, 2019-04)
Selective C-C coupling of oxygenates is pertinent to the manufacture of fuel and chemical products from biomass and from derivatives of C 1 compounds (i.e., oxygenates produced from methane and CO 2 ). Here we report a ...
Oxygen vacancies and peroxo groups on regular and low-coordinated sites of MgO, CaO, SrO, and BaO surfaces
(Elsevier Science, 2006-03)
The formation of an oxygen vacancy and the simultaneous re-adsorption of an oxygen atom on regular and low-coordinated (LC) sites (edges and corners) of the surface of alkaline-earth oxides with cubic rock salt structure, ...
Low-frequency ultrasound induces oxygen vacancies formation and visible light absorption in TiO 2 P-25 nanoparticles
(Elsevier, 2012-05)
Low-frequency ultrasound (LFUS) irradiation induces morphological, optical and surface changes in the commercial nano-TiO 2-based photocatalyst, Evonik-Degussa P-25. Low-temperature electron spin resonance (ESR) measurements ...
Iron and oxygen vacancies at the hematite surface: Pristine case and with a chlorine adatom
(Royal Society of Chemistry, 2020-11)
Defect complexes play critical roles in the dynamics of water molecules in photoelectrochemical cell devices. For the specific case of hematite (α-Fe2O3), iron and oxygen vacancies are said to mediate the water splitting ...
Effect of nearest neighbor Pb-O divacancy pairs on the ferroelectric-relaxor transition in Pb(Sc1/2Nb1/2)O3
(American Physical Society, 2008-12)
Molecular dynamics simulations were performed on a frst-principles-based effective Hamiltonian for Pb(Sc1/2Nb1/2)O3 (PSN) with nearest neighbor Pb-O divacancy pairs. Simulations were performed for PSN with ideal chemical ...
Oxygen related defects and vacancy clusters identified in sputtering grown UOx thin films by positron annihilation techniques
(Elsevier, 2021-08)
We experimentally studied the formation of vacancy clusters and oxygen related defects in uranium oxide (UOx) thin films (<70 nm) changing the stoichiometry in the x = 2.2?3.5 range. Films were deposited on Si(0 0 1) by ...