XPS study of the chemical stability of DyBa2Cu3O6+δ superconductor

Abstract

The chemical stability of the powder DyBa 2 Cu 3 O 6+ has been studied by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and thermal analysis at ambient conditions. The powder was subjected to mechanical processing in a ball mill-activator to accelerate chemical degradation. The kinetic regularities of hydrolytic decomposition of DyBa 2 Cu 3 O 6+ under the influence of air moisture have been determined. The resistive properties of DyBa 2 Cu 3 O 6+ to water have been found to be better, but not much different from analogous properties of YBa 2 Cu 3 O 6+ which is unstable in a wet environment. Chemical degradation of the material is triggered by crucial concentrating of water particles near the free surface of the solid reactant (due to their low diffusibility in the bulk) leading to rapid chemical decomposition of the respective regions.

Surface Morphological and Chemical Features of Anticorrosion ZrO2–TiO2 Coatings: Impact of Zirconium Precursor

“…The O1s peaks were broad and asymmetric, and they could be deconvoluted by a Lorentzian-Gaussian curve fitting into two components (Figure 11). The first ones at ~529.8 eV were assigned to lattice oxygen in ZrO 2 and TiO 2 , and the second ones at ~531.4 eV were attributed to adsorbed hydroxyl groups [41,42]. The Ti2p spectra had peaks at ~458.3 eV for Ti2p 3/2 and ~464.0 eV for Ti2p 1/2 .…”

“…eV were attributed to adsorbed hydroxyl groups [41,42]. The Ti2p spectra had peaks at ~458.3 eV for Ti2p3/2 and ~464.0 eV for Ti2p1/2.…”

Distance to Massive Metal Body—a Paradoxical Parameter that Regulates the Intensity of the Hydration of YBa2Cu3O6.75

“…In our previous work [5], we studied the hydration of YBa 2 Cu 3 O 6.75 (YBCO) which is a superconductor with a critical temperature of about 70 K. This compound is chemically active with respect to water and as a result of prolonged contact with a moist environment can chemically degrade, losing its practical performance properties [6,7]. In [5], however, we used a previously developed method of material preparation, such one that enables hydration process in the final product to proceed at relatively low p H 2 O (0.9-1.0 kPa), which is unrealistic for the other methods.…”

Dissolution-regrowth of hierarchical Fe-Dy oxide modulates the electronic structure of nickel-organic frameworks as highly active and stable water splitting electrocatalysts

“…In the high-resolution Dy 3d5/2 spectrum of FeDy@MOF-Ni in Fig. 4c, a peak corresponding to Dy2O3 was fitted at 1297.0 eV [47,48]; this peak was shifted 0.70 eV toward lower binding energy compared with that of Dy@MOF-Ni, which could be due to the effect of the surface enrichment of Ni and Fe species on the charge density around the Dy species. These results indicate that the content of high-valence Ni and Fe species was remarkably improved in FeDy@MOF-Ni by the participation of Dy species.…”