Understanding the stability and reactivity of iron sulfide phases is key to developing predictive capabilities for assessing their corrosion and catalytic activity. The differences between the free surface and the bulk interior of such phases are of particular importance in this context. Here, we employ density functional theory to investigate the formation energetics and electronic structure o...

The thermodynamic redox properties of ceria and ceria zirconia solid solutions are analysed with a new methodology for modelling such systems based on the statistical mechanics of lattice configurations. Experimental thermogravimetric equilibrium data obtained for small non-stoichiometry measurements are combined with literature data to cover a large range of non-stoichiometry (CeO2-δ, δ = 0.00...

An embedded-atom potential has been constructed for the intermetallic compound B2-NiAl by fitting to both experimental properties and ab initio data. The ab initio data have been generated in the form of energy-volume relations for a number of alternative structures of NiAl and Ni3Al, as well as for Ni and Al. The potential accurately reproduces the basic lattice properties of B2-NiAl, planar f...

The demand for clean and sustainable energy has garnered great interest in new materials. Among them, high temperature proton-conducting perovskite oxides are, or can be widely used applications (including fuel cells, electrochemical reactors, solid-state separators supports of catalytic components via various reduction oxidation reactions) the intermediate range. control defect chemistry is ma...

The dependences of electrical conductivity, the Hall coefficient, Seebeck thermoelectric power factor and microhardness Bi2Se3 polycrystals on degree deviation from stoichiometry 59.9–60.0 at. % Se temperature (77–300 K) were obtained. samples exhibited n-type conductivity in studied ranges compositions temperatures. boundaries homogeneity region estimated. A non-monotonic behavior concentratio...

The Ba0.985La0.015Ti0.9Sn0.1O3 ceramic has been prepared by a cost-effective solid-state reaction method. Preliminary room-temperature X-ray diffraction indicates that the crystallization of is good. Field Emission Scanning Electron Microscopy was used to study microstructure ceramic. photoelectron spectroscopy characterize oxygen vacancies. Dielectric properties and impedance reflected charact...

In this work, doping-defect interactions relevant to self-compensation in p-type GaN were investigated using atom probe tomography. The 3D visualization of ion distribution revealed the formation spherical Mg-rich clusters and segregation Mg dopant towards dislocations MOCVD-grown GaN:Mg. Impurities related self-compensation, such as oxygen hydrogen, identified detected adjacent dislocations. C...

In a theoretical study of a "defect perovskite" structure of stoichiometry AeTiO(2) (AE = alkaline earth metal, Be, Mg, Ca, Sr, and Ba), we find substantial Ti-Ti bonding tuned by the size of the Ae(2+) cation. The bonding is one-dimensional, partially sigma, partially pi. These formal d(2) systems are expected to be nonmagnetic and metallic. A competing (for same Ae) structural alternative, an...

Iron pyrite (fool's gold, FeS₂) is a promising earth abundant and environmentally benign semiconductor material that shows promise as a strong and broad absorber for photovoltaics and high energy density cathode material for batteries. However, controlling FeS₂ nanocrystal formation (composition, size, shape, stoichiometry, etc.) and defect mitigation still remains a challenge. These problems r...