Influence of Local Defects on the Dynamics of O-H Bond Breaking and Formation on a Magnetite Surface

Abstract

The transport of H adatoms across oxide supports plays an important role in many catalytic reactions. We investigate the dynamics of H/Fe3O4(001) between 295 and 382 K. By scanning tunneling microscopy at frame rates of up to 19.6 fps, we observe the thermally activated switching of H between two O atoms on neighboring Fe rows. This switching rate changes in proximity to a defect, explained by density functional theory as a distortion in the Fe-O lattice shortening the diffusion path. Quantitative analysis yields an apparent activation barrier of 0.94 +/- 0.07 eV on a pristine surface. The present work highlights the importance of local techniques in the study of atomic-scale dynamics at defective surfaces such as oxide supports.

References in corpus (14)

• Van der Waals Density Functional for General Geometries
• A Higher-Accuracy van der Waals Density Functional
• Efficient implementation of a van der Waals density functional: Application to double-wall carbon nanotubes
• Perspective: How good is DFT for water?
• Iron Oxide Surfaces
• CO Induced Adatom Sintering in a Model Catalyst: Pd/Fe3O4
• Subsurface Cation Vacancy Stabilization of the Magnetite (001) Surface
• Water Agglomerates on Fe3O4(001)
• An Atomic-Scale View of CO and H2 Oxidation on a Pt-Fe3O4 Model Catalyst
• Surface properties of the clean and Au/Pd covered Fe${}_3$O${}_4$(111): a DFT and DFT+$U$ study
• The role of surface defects in the adsorption of methanol on Fe3O4(001)
• Adsorption of CO on the Fe3O4(001) Surface
• The new FAST module: a portable and transparent add-on module for time-resolved investigations with commercial scanning probe microscopes
• Order-disorder phase transition on the (100) surface of magnetite

Cited by in corpus (4)

• Atomic-scale studies of Fe3O4(001) and TiO2(110) surfaces following immersion in CO2-acidified water
• Mechanism of spin ordering in Fe${}_3$O${}_4$ nanoparticles by surface coating with organic acids
• PyfastSPM: A Python package to convert 1D FastSPM data streams into publication quality movies
• A Multi-Technique Study of C2H4 Adsorption on a Model Single-Atom Rh1 Catalyst