Surface structure and reactivity of
multi-component oxides at the atomic scale

Subproject P02

Multi-component metal oxides exhibit a plethora of stoichiometry-dependent structural phases at the surface, even if the composition of the bulk is kept the same. The long-term objective of P02 is to unravel the relationship between surface electronic and geometric structure and reactivity, to ultimately tune these materials for energy-related reactions such as the ORR. The project applies the surface science approach. We will grow well-defined, epitaxial perovskite thin films of LSFO and LSMO in a UHV-based PLD/surface science apparatus under tight control of the surface stoichiometry in the first project period. We will determine the coordinates of surface atoms quantitatively using LEED-IV in close collaboration with theoretical groups.

Theoretical models will also help with interpreting atomically-resolved ncAFM/STM images. These images give direct insights into the behavior of polarons in these complex materials and show how adsorbates such as O2, H2O, CO, and CO2 interact with electronic and structural defects. XPS, TPD, and FTIR of these well-defined systems will deliver desorption energies, vibrational frequencies, and spectral fingerprints. These experimental data on well-defined systems will build a bridge when tested under ‘realistic’ environments at high pressure/temperature and in aqueous solutions. They will also serve to validate ML-based theory approaches.

Ulrike Diebold
PI

Expertise

Our expertise is experimental surface science. We operate a total of seven ultrahigh-vacuum (UHV) chambers, which contain virtually all main experimental surface science techniques, as well as an (electro-)chemistry lab.

All chambers are equipped with facilities for sample preparation (sputtering/annealing/gas dosing), as well as various growth techniques (e-beam evaporators, Knudsen cells, UHV-compatible sputter deposition, pulsed laser deposition (PLD)).

Analysis techniques used in our research include:

  • Scanning Tunneling Microscopy (STM) (in UHV 4K – 300 K, electrochemical STM)
  • Atomic Force Microscopy (AFM): UHV-based (q+ sensor) and in the ambient (cantilever-based)
  • Low-Energy Electron Diffraction (LEED)
  • Reflection High Energy Diffraction (RHEED)
  • X-ray Photoelectron Spectroscopy (XPS)
  • Ultraviolet Photoelectron Spectroscopy (UPS)
  • Auger Electron Spectroscopy (AES)
  • Low-energy He+ ion scattering (LEIS)
  • Thermal Programmed Desorption Spectroscopy (TPD)

Of particular use for TACO is our combined Pulsed-Laser Deposition/Surface Science setup shown on the right-hand side. It allows the growth of multi-component metal oxides and the investigations of surface properties within the same UHV setup.

Team

Ulrike Diebold
PI

Michele Riva
co-PI

Michael Schmid
co-PI

Alexander Michael Imre
PhD Student

Erik Rheinfrank
PhD Student

Florian Dörr
Master Student

Former Members

Michael Brunthaler
Master Student

Publications

19 entries « 1 of 2 »

2022

Surface chemistry on a polarizable surface: Coupling of CO with KTaO 3(001)

Wang, Zhichang; Reticcioli, Michele; Jakub, Zdenek; Sokolović, Igor; Meier, Matthias; Boatner, Lynn A; Schmid, Michael; Parkinson, Gareth S; Diebold, Ulrike; Franchini, Cesare; Setvin, Martin

Surface chemistry on a polarizable surface: Coupling of CO with KTaO 3(001)

Journal ArticleOpen Access

In: Science Advances, vol. 8, iss. 33, 2022.

Abstract | Links | BibTeX | Tags: P02, P04, P07

Competing electronic states emerging on polar surfaces

Reticcioli, Michele; Wang, Zhichang; Schmid, Michael; Wrana, Dominik; Boatner, Lynn A.; Diebold, Ulrike; Setvin, Martin; Franchini, Cesare

Competing electronic states emerging on polar surfaces

Journal ArticleOpen Access

In: Nature Communications, vol. 13, no. 4311, 2022.

Abstract | Links | BibTeX | Tags: P02, P07

Machine learning for exploring small polaron configurational space

Birschitzky, Viktor C; Ellinger, Florian; Diebold, Ulrike; Reticcioli, Michele; Franchini, Cesare

Machine learning for exploring small polaron configurational space

Journal ArticleOpen Access

In: npj Computational Materials, vol. 8, no. 125, 2022.

Abstract | Links | BibTeX | Tags: P02, P07

Structure of an Ultrathin Oxide on Pt3Sn(111) Solved by Machine Learning Enhanced Global Optimization

Merte, Lindsay R; Bisbo, Malthe Kjær; Sokolović, Igor; Setvín, Martin; Hagman, Benjamin; Shipilin, Mikhail; Schmid, Michael; Diebold, Ulrike; Lundgren, Edvin; Hammer, Bjørk

Structure of an Ultrathin Oxide on Pt3Sn(111) Solved by Machine Learning Enhanced Global Optimization

Journal ArticleOpen Access

In: Angewandte Chemie - International Edition, vol. 61, iss. 25, pp. e202204244, 2022.

Abstract | Links | BibTeX | Tags: P02

CO oxidation by Pt2/Fe3O4: Metastable dimer and support configurations facilitate lattice oxygen extraction

Meier, Matthias; Hulva, Jan; Jakub, Zdenek; Kraushofer, Florian; Bobić, Mislav; Bliem, Roland; Setvin, Martin; Schmid, Michael; Diebold, Ulrike; Franchini, Cesare; Parkinson, Gareth S

CO oxidation by Pt2/Fe3O4: Metastable dimer and support configurations facilitate lattice oxygen extraction

Journal ArticleOpen Access

In: ScienceAdvances, vol. 8, iss. 13, pp. eabn4580, 2022.

Abstract | Links | BibTeX | Tags: P02, P04, P07

Modeling polarons in density functional theory: lessons learned from TiO2

Reticcioli, Michele; Diebold, Ulrike; Franchini, Cesare

Modeling polarons in density functional theory: lessons learned from TiO2

Journal ArticleOpen Access

In: Journal of Physics: Condensed Matter, vol. 34, no. 20, pp. 204006, 2022.

Abstract | Links | BibTeX | Tags: P02, P07

Reconstruction changes drive surface diffusion and determine the flatness of oxide surfaces

Franceschi, Giada; Schmid, Michael; Diebold, Ulrike; Riva, Michele

Reconstruction changes drive surface diffusion and determine the flatness of oxide surfaces

Journal ArticleOpen Access

In: Journal of Vacuum Science & Technology A, vol. 40, no. 2, pp. 023206, 2022.

Abstract | Links | BibTeX | Tags: P02

Why and How Savitzky–Golay Filters Should Be Replaced

Schmid, Michael; Rath, David; Diebold, Ulrike

Why and How Savitzky–Golay Filters Should Be Replaced

Journal ArticleOpen Access

In: ACS Measurement Science Au, vol. 2, no. 2, pp. 185–196, 2022.

Abstract | Links | BibTeX | Tags: P02

2021

Two-dimensional surface phase diagram of a multicomponent perovskite oxide: La0.8Sr0.2MnO3 (110)

Franceschi, Giada; Schmid, Michael; Diebold, Ulrike; Riva, Michele

Two-dimensional surface phase diagram of a multicomponent perovskite oxide: La0.8Sr0.2MnO3 (110)

Journal Article

In: Physical Review Materials, vol. 5, no. 9, pp. L092401, 2021.

Abstract | Links | BibTeX | Tags: P02

Ni-modified Fe3O4(001) surface as a simple model system for understanding the oxygen evolution reaction

Mirabella, Francesca; Müllner, Matthias; Touzalin, Thomas; Riva, Michele; Jakub, Zdenek; Kraushofer, Florian; Schmid, Michael; Koper, Marc T M; Parkinson, Gareth S; Diebold, Ulrike

Ni-modified Fe3O4(001) surface as a simple model system for understanding the oxygen evolution reaction

Journal ArticleOpen Access

In: Electrochimica Acta, vol. 389, pp. 138638, 2021.

Abstract | Links | BibTeX | Tags: P02, P04, pre-TACO

19 entries « 1 of 2 »