Composition and structure of Pd nanoclusters in SiOx_x thin film

The nucleation, distribution, composition and structure of Pd nanocrystals in SiO$_2$ multilayers containing Ge, Si, and Pd are studied using High Resolution Transmission Electron Microscopy (HRTEM) and X-ray Photoelectron Spectroscopy (XPS), before and after heat treatment. The Pd nanocrystals in the as deposited sample seem to be capped by a layer of PdO$_x$. A 1-2 eV shift in binding energy was found for the Pd-3d XPS peak, due to initial state Pd to O charge transfer in this layer. The heat treatment results in a decomposition of PdO and Pd into pure Pd nanocrystals and SiO$_2$

Surface reactivity and cation non-stoichiometry in BaZr_1−xY_xO_3−δ (x = 0–0.2) exposed to CO₂ at elevated temperature

The reactivity of BaZr1−xYxO3−δ (x = 0–0.2) ceramics under 1 atm CO2 at 650 °C for up to 1000 h was investigated in order to elucidate possible degradation processes occurring when the material is applied as a proton-conducting electrolyte in electrochemical devices. The annealed ceramics were characterized by a range of techniques (SEM, TEM, GIXRD, XPS and SIMS) with respect to changes in the phase composition and microstructure. Formation of BaCO3 was observed on the surfaces of the annealed samples and the amount increased with time and was higher for the Y-doped compositions. The subsurface regions were found to be deficient in Ba and, in the case of the Y-doped compositions, enriched in Y in two distinct chemical states as identified by XPS. First-principles calculations showed that they were Y residing on the Zr and Ba-sites, respectively, and that local enrichment of Y both in bulk and on the surface attained a structure similar to Y2O3. Overall, it was substantiated that the reaction with CO2 mainly proceeded according to a defect chemical reaction involving transfer of Y to the Ba-site and consumption of BaZrO3 formula units. It was suggested that a similar degradation mechanism may occur in the case of Ba(OH)2 formation under high steam pressure conditions

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Data for "High yield and wide lateral size growth of α-Mo2C: Exploring the boundaries of CVD growth of bare MXene analogues"

Images and data underlying the results in published scientific paper "High yield and wide lateral size growth of α-Mo2C: Exploring the boundaries of CVD growth of bare MXene analogues" (DOI 10.1088/1361-6528/ad1c97)</p