Atomic Scale Insights into Reversible Oxygen Storage in Vanadium Oxide Thin Films

Chemphyschem. 2024 Apr 3:e202300988. doi: 10.1002/cphc.202300988. Online ahead of print.ABSTRACTMonolayer vanadium oxide films grown on Pt(111) supports can be reversibly switched between an oxygen-poor and an oxygen-rich composition, equivalent to V2O3 and V2O4.5, respectively. While the overall oxygen storage capacity of the film is quantified by X-ray photoelectron spectroscopy, the atomic-scale binding sites of the excess O species are determined by low-temperature scanning tunneling microscopy and electron diffraction. In the O-poor phase, the oxide takes the form of a honeycomb lattice that gets partially covered with vanadyl (V=O) groups at higher O exposure. Upon transition to the O-rich phase, isolated V6O12 rings emerge first in the film, which then evolves gradually towards a disordered O-V-O trilayer on the Pt(111) surface. Our works thus unravels the microscopic nature of reversible oxygen storage in a model system for heterogeneous catalysis.PMID:38568865 | DOI:10.1002/cphc.202300988

Source: Chemphyschem - April 3, 2024 Category: Chemistry Authors: Ghada Missaoui Piotr Igor Wemhoff Niklas Nilius Source Type: research