Structural Characterization of LaSrCoO Thin Films Grown on (100)-, (110)-, and (111)-Oriented LaSrGaMgO.

In this study, a detailed structural characterization of epitaxial La0.6Sr0.4CoO3-δ (LSC) films grown in (100), (110), and (111) orientations was conducted.

Chemical capacitance measurements reveal the impact of oxygen vacancies on the charge curve of LiNiMnO thin films.

The level of oxygen deficiency in high-voltage spinels of the composition LiNiMnO (LNMO) significantly influences the thermodynamic and kinetic properties of the material, ultimately affecting the cell performance of the corresponding lithium-ion batteries. This study presents a comprehensive defect chemical analysis of LNMO thin films with oxygen vacancy concentrations of 2.4% and 0.

Defect Chemistry of Spinel Cathode Materials-A Case Study of Epitaxial LiMnO Thin Films.

Spinels of the general formula LiMO are an essential class of cathode materials for Li-ion batteries, and their optimization in terms of electrode potential, accessible capacity, and charge/discharge kinetics relies on an accurate understanding of the underlying solid-state mass and charge transport processes. In this work, we report a comprehensive impedance study of sputter-deposited epitaxial LiMnO thin films as a function of state-of-charge for almost the entire tetrahedral-site regime (1 ≤ δ ≤ 1.9) and provide a complete set of electrochemical properties, consisting of the charge-transfer resistance, ionic conductivity, volume-specific chemical capacitance, and chemical diffusivity.

Crystal-Orientation-Dependent Oxygen Exchange Kinetics on Mixed Conducting Thin-Film Surfaces Investigated by Studies.

The oxygen exchange kinetics and the surface chemistry of epitaxially grown, dense LaSrCoO (LSC) thin films in three different orientations, (001), (110), and (111), were investigated by means of impedance spectroscopy during pulsed laser deposition (i-PLD) and near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS). i-PLD measurements showed that pristine LSC surfaces exhibit very fast surface exchange kinetics but revealed no significant differences between the specific orientations. However, as soon as the surfaces were in contact with acidic, gaseous impurities, such as S-containing compounds in nominally pure measurement atmospheres, NAP-XPS measurements revealed that the (001) orientation is substantially more susceptible to the formation of sulfate adsorbates and a concomitant performance decrease.

electrochemical observation of anisotropic lattice contraction of LaSrFeO electrodes during pulsed laser deposition.

LaSrFeO (LSF) electrodes were grown on different electrolyte substrates by pulsed laser deposition (PLD) and their oxygen exchange reaction (OER) resistance was tracked in real-time by PLD impedance spectroscopy (i-PLD) inside the PLD chamber. This enables measurements on pristine surfaces free from any contaminations and the direct observation of thickness dependent properties. As substrates, yttria-stabilized zirconia single crystals (YSZ) were used for polycrystalline LSF growth and LaSrGaMgO (LSGM) single crystals or YSZ single crystals with a 5 nm buffer-layer of GdCeO for epitaxial LSF film growth.