In situ diffraction monitoring of nanocrystals structure evolving during catalytic reaction at their surface.

ABSTRACT: With decreasing size of crystals the number of their surface atoms becomes comparable to the number of bulk atoms and their powder diffraction pattern becomes sensitive to a changing surface structure. On the example of nanocrystalline gold supported on also nanocrystalline [Formula: see text] we show evolution of (a) the background pattern due to chemisorption phenomena, (b) peak positions due to adsorption on nonstoichiometric [Formula: see text] particles, (c) Au peaks intensity. The results of the measurements, complemented with mass spectrometry gas analysis, point to (1) a multiply twinned structure of gold, (2) high mobility of Au atoms enabling transport phenomena of Au atoms to the surface of ceria while varying the amount of Au in the crystalline form, and (3) reversible [Formula

SUBMITTER: Zielinski M 

PROVIDER: S-EPMC9879985 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature