Stability and charge transfer in the misfit compound (LaS)(SrS)0.2CrS2: Ab initio band-structure calculations
摘要:
Local-density approximation ab initio band-structure calculations have been carried out on the misfit compound (LaS)(SrS)(0.2)CrS2. It appears that this phase can be regarded as an infinite two-dimensional intercalation compound. One electron is transferred from the LaS slab to the CrS2 slab. For the (LaS) (La2/3(1-y)SryS)(0.2)CrS2 derivatives Sr atoms can substitute La atoms up to y=1. This study confirms the existence of La vacancies in the nondoped compound and is consistent with the observed nonmetallic character of this phase.
The vaporization of LaCrOsub 3}(s) and samples of the composition LaCrOsub 3} + Lasub 2}Osub 3} was investigated in the temperature range of 1,887--2,333 K by Knudseneffusionmassspectrometry using Knudsen cells made of tungsten lined completely with iridium. The species Cr(g), CrO(g), CrOsub 2}(g), and LaO(g) were identified in the vapor. Their partial pressures were determined by calibration
Influence of transition metal electronegativity on the oxygen storage capacity of perovskite oxides
作者:Lu Liu、Daniel D. Taylor、Efrain E. Rodriguez、Michael R. Zachariah
DOI:10.1039/c6cc01997h
日期:——
The selection of highly efficient oxygen carriers (OCs) is a key step necessary for the practical development of chemical looping combustion (CLC).
高效氧载体(OCs)的选择是化学环路燃烧(CLC)实际发展所必需的关键步骤。
Pressure-induced charge transfer in lanthanum nickel ferrate () and analogies to composition-driven charge transfer in dilanthanum cuprate : an infrared study
作者:Richard Mortimer、James G Powell、Nagasampagi Y Vasanthacharya
DOI:10.1088/0953-8984/9/50/021
日期:1997.12.15
A reversible pressure-induced phasetransition in lanthanum nickel ferrate (LaNi0.5Fe0.5O3) manifests itself in the infrared spectrum of the transition metal-oxygen stretching (nu(TM-O)) modes by the emergence of new peaks at pressures greater than similar to 1.4 x 10(9) Pa. Analogies to this transition are made by considering charge transfer in dilanthanum cuprate (La2CuO4) and its modification by
高铁酸镧镍 (LaNi0.5Fe0.5O3) 中的可逆压力诱导相变通过在压力大于类似于 1.4 x 10(9) Pa。通过考虑铜酸二镧 (La2CuO4) 中的电荷转移及其通过铬离子部分取代铜离子进行的修改,可以模拟这种转变。
Structure, Electrical Properties, and Surface Reactivity of CVD-Made Functional Complex Oxides
Besides the near-bulk properties of 250 nm thick perovskites, an unusual surface confinement of charge transport was observed in ultrathin, < 10 nm, polycrystalline LaCoO3 films, resulting in an electrical resistivity that appears to be lower than that of a single crystal. Using doping strategy as a tool to tune the physicochemical properties of the spinel structure of cobalt oxide was demonstrated, enabling
Physicochemical properties of rare earth perovskite oxides used as gas sensor material
作者:Tsuyoshi Arakawa、Hiroshi Kurachi、Jiro Shiokawa
DOI:10.1007/bf01026315
日期:1985.4
The change of the conductivity in the rare earth perovskiteoxide took place after the chemisorption of flammable gases. The sensitivity for methanol was highest. From the conductivity change of these perovskiteoxides after the injection of methanol, the energy needed to promote an electron from a conducting to a nonconducting state, ΔE=Ec-Et, could be derived from the equationσ=Aσ0 exp (−ΔE/kT).