相关论文: Atomic-scale insights into electro-steric substitu…
According to defect chemistry, the experimental observations of enhanced cation diffusion in a reducing atmosphere in zirconia, ceria and barium titanate are in support of an interstitial mechanism. Yet previous computational studies always…
Understanding the electronic charge distribution around oxygen vacancies in transition metal and rare earth oxides is a scientific challenge of considerable technological importance. We show how significant information about the charge…
Rare-earth doped form, ceria (CeO2) is of interest as a potential candidate for solid oxide fuel cells (SOFCs) because of its relatively high oxygen ion conductivity at temperatures below 600 {\deg}C. At the present time, computational…
Oxide interfaces play very important roles for the physical and chemical properties of nanostructured materials, such as an ionic conductivity, superconductivity, and magnetism. Gadolinia-doped Ceria (GDC) is commonly selected as the…
Some oxygen defective metal oxides, such as cerium and bismuth oxides, have recently shown exceptional electrostrictive properties that are even superior to the best performing lead-based electrostrictors, e.g. lead-magnesium-niobates…
Cubic yttria-stabilized zirconia is widely used in industrial electrochemical devices. While its fast oxygen ion diffusion is well understood, why cation diffusion is much slower-its activation energy (~5 eV) is 10 times that of anion…
Ion diffusion is a central part of materials physics of fabrication, deformation, phase transformation, structure stability and electrochemical devices. Conventional theory focuses on the defects that mediate diffusion and explains how…
In light of the recent discovery of giant electrostriction in defective fluorites, here we investigate the interplay between mechanical, electrochemical and electromechanical properties of oxygen defective ceria compositions as the effect…
Ceria (CeO$_2$) is a material of significant technological importance. A detailed understanding of the material's defect physics and chemistry is key to understanding and optimizing its properties. Here, we report a hybrid…
The efficacy of the electrical conductivity relaxation (ECR) technique for investigating the oxygen transport properties of mixed conducting oxides has been evaluated. Fifteen mol% samarium doped ceria (SDC15), for which approximate values…
We perform an electronic structure study for cerium oxide homogeneously-doped with cobalt impurities, focusing on the role played by oxygen vacancies and structural relaxation. By means of full-potential ab-initio methods, we explore the…
This article is devoted to investigation of cation self-diffusion mechanisms, taking place in UO2, UO2+x, and UO2-x crystals simulated under periodic (PBC) and isolated (IBC) boundary conditions using the method of molecular dynamics in the…
The stoichiometric antiferromagnetic insulator EuTiO$_3$ is proximate to a ferroelectric phase. Whereas cation substitution has been used as a tuning parameter to introduce charge carriers and manipulate the magnetism, the effects of…
A comprehensive analysis is presented for the diffusivity of oxygen defects and oxygen self-diffusion in ThO$-2$. The migration energy and diffusivity of oxygen defects with nominal charges have been investigated using density functional…
In the quest of green energy, Solid Oxide Fuel Cells (SOFC) have drawn considerable attention for chemical-to-electric energy conversion. In the present paper, we report an enhancement of ionic conductivity in Cu2P2-xVxO7 by vanadium…
Highly efficient oxygen active materials that react with, absorb, and transport oxygen is essential for fuel cells, electrolyzers and related applications. While vacancy mediated oxygen ion conductors have long been the focus of research,…
Cerium and its technologically relevant compounds are examples of anomalous mixed valency, originating from two competing oxidation states -- itinerant Ce$^{3+}$ and localized Ce$^{4+}$. Under applied stress, anomalous transitions are…
A theoretical modeling of the oxygen diffusivity in silicon and germanium crystals both at normal and high hydrostatic pressure has been carried out using molecular mechanics, semiempirical and ab initio methods. It was established that the…
Highly oxygen defective cerium oxide, e.g. Gd-doped ceria is a sustainable non-classical electrostrictor with electromechanical properties that are superior to lead-based piezoelectric metal oxides. Here, we report electrostriction in…
We used classical and accelerated molecular dynamics simulations to characterize vacancy-mediated diffusion of cations in Gd$_2$Ti$_2$O$_7$ pyrochlore as a function of the disorder on the microsecond timescale. We find that cation vacancy…