We investigate the dopant distribution and its influence on the oxygen ion conductivity of ceria doped with rare earth oxides by combining density functional theory and Monte Carlo simulations. We calculate the association energies of dopant pairs, oxygen vacancy pairs and between dopant ions and oxygen vacancies by means of DFT + U including finite size corrections. The cation coordination num...

Nanowires (NWs) have been extensively studied over the last few decades for both scientific interest and technological potential. Semiconductor NWs’ physical properties are profoundly dependent on their chemical composition and especially so on their dopant concentration, profiles and activity level. Controlling NWs axial and radial dopant profiles is, therefore, of utmost importance for NW-bas...

As the gate length of MOSFET devices shrinks down below 100 nm, the fluctuation of major devices parameter, namely, threshold voltage (VTH), subthreshold swing, drain current (ID) and subthreshold leakage current due to influences of processes variations becomes a serious problem. Random dopant fluctuation is one of the problems. In this work, we numerically examine the fluctuation effects of r...

The sensitive dependence of a semiconductor's electronic, optical and magnetic properties on dopants has provided an extensive range of tunable phenomena to explore and apply to devices. Recently it has become possible to move past the tunable properties of an ensemble of dopants to identify the effects of a solitary dopant on commercial device performance as well as locally on the fundamental ...

A theoretical study of geometry, stability, electronic structure, and magnetic property neutral Al16M clusters with M being a first-row 3d transition metal atom, including Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, are investigated in this using quantum chemical approaches. The favor three kind structures based on pure Al17 framework, two exohedral doped isomers one endohedral structure. There is c...

Highly efficient platinum-group metal (PGM)-free electrocatalysts are essential for the large-scale utilization of Zn-air batteries (ZABs). Herein, we report simple fabrication a single atomic PGM-free electrocatalyst, Fe-SA/N-C, via post-synthetic electrostatic absorption (PSEA) strategy. The Fe atoms anchored on three-dimensiaonal (3D) porous carbon with adjacent N atoms, forming Fe-N4 active...

Local fluctuations in the distribution of dopant atoms are thought to cause the nanoscale electronic disorder or phase separation in pnictide superconductors. Atom probe tomography has enabled the first direct observations of dopant species clustering in a K-doped 122-phase pnictide. First-principles calculations suggest the coexistence of static magnetism and superconductivity on a lattice par...

TiO2 nanorods can be used as dye-sensitized solar cells and as various sensors and photocatalysts. These nanorods are synthesized by a using thermal corrosion process in a NaOH solution at 200 oC with TiO2 powder as a source material. In the present work, the synthesis of TiO2 nanorods in anatase, rutile and Ti8O15 phases and the...

using ab initio calculations, the hydrogen desorption from magnesium hydride (mgh2) was studied. we presented the calculated nuclear quadrupole coupling constants (nqccs) of hydrogen atom in various systems of mgh2. the effect of interactions of some metal atoms as well as boron atom with mgh2 host matrix; (mgh2+m) nanostructures (m=al, ti, v, fe, ni and b); were studied and 2h-nqccs were calcu...

To lower the introduction and maintenance costs of autonomous power supplies for driving Internet-of-things (IoT) devices, we have developed low-cost Fe–Al–Si-based thermoelectric (FAST) materials generation modules. Our development approach combines computational science, experiments, mapping measurements, machine learning (ML). FAST a good balance mechanical properties excellent chemical stab...