info:eu-repo/semantics/article
Electrochemical stability of the reconstructed Fe3O4(001) surface
Date
2020-12-01Registration in:
Grumelli, Doris Elda; Wiegmann, Tim; Barja, Sara; Reikowski, Finn; Maroun, Fouad; et al.; Electrochemical stability of the reconstructed Fe3O4(001) surface; Wiley-VCH; Angewandte Chemie; 132; 49; 1-12-2020; 22088-22092
0044-8249
1521-3757
CONICET Digital
CONICET
Author
Grumelli, Doris Elda
Wiegmann, Tim
Barja, Sara
Reikowski, Finn
Maroun, Fouad
Allongue, Philippe
Balajka, Jan
Parkinson, Gareth S.
Diebold, Ulrike
Kern, Klaus
Magnussen, Olaf M.
Abstract
Establishing the atomic-scale structure of metaloxide surfaces during electrochemical reactions is a key step to modeling this important class of electrocatalysts. Here, we demonstrate that the characteristic (p2p2)R458 surface reconstruction formed on (001)-oriented magnetite single crystals is maintained after immersion in 0.1 M NaOH at 0.20 V vs. Ag/AgCl and we investigate its dependence on the electrode potential. We follow the evolution of the surface using in situ and operando surface X-ray diffraction from the onset of hydrogen evolution, to potentials deep in the oxygen evolution reaction (OER) regime. The reconstruction remains stable for hours between 0.20 and 0.60 V and, surprisingly, is still present at anodic current densities of up to 10 mA cm2 and strongly affects the OER kinetics. We attribute this to a stabilization of the Fe3O4 bulk by the reconstructed surface. At more negative potentials, a gradual and largely irreversible lifting of the reconstruction is observed due to the onset of oxide reduction.