Catalytic Oxidation on Metal-Supported Oxide Films

Metal-supported oxide films serve as model heterogeneous catalysts that bridge fundamental surface science and practical applications in emission control, air purification and chemical synthesis. By depositing atomically thin layers of reducible oxides (for example FeOx, CoOx or TiOx) onto well-defined metal substrates, researchers can probe interfacial charge transfer, dynamic restructuring and reaction mechanisms at the atomic scale. Key features include the tunable oxide stoichiometry, the formation of oxygen vacancies and the emergence of strong metal–support interactions that alter electronic states at the boundary. Oxidation reactions often proceed via a Mars–van Krevelen mechanism whereby lattice oxygen directly participates in substrate conversion, creating vacancies that are subsequently replenished by gaseous O2. Operando spectroscopies and theoretical simulations have revealed multiple active phases that evolve with temperature, gas composition and film thickness. This body of work provides guiding principles for rational catalyst design, offering routes to enhance activity, selectivity and stability through precise control of interfacial structure and chemistry.

Research from Nature Portfolio

Recent studies have delineated the evolution of active phases in cobalt oxide films supported on Au(111). Under varying CO/O2 ratios and temperatures, partially reduced CoOx films containing metallic Co prevail as active species at lower temperatures, whereas stoichiometric CoO phases form surface carbonates that inhibit activity. Oxygen-rich conditions give rise to Co3+-rich films that remain highly active over a broad temperature window. Resonant photoemission and density functional theory calculations clarify the role of interfacial Co3+ sites in facilitating O2 activation and lowering energy barriers for CO oxidation.

An alternative design exploits electron penetration in a graphene-isolated Pt catalyst derived from CoNi nanoparticles. The ultrathin graphene shell protects the underlying alloy from oxidation while enabling electronic modulation of the Pt–graphene interface. This architecture achieves near-complete CO conversion at room temperature by segregating CO adsorption on Pt from O2 activation at the interface, thus offering a novel paradigm distinct from classical metal–oxide systems.

Catalytic Oxidation on Metal-Supported Oxide Films publication trend

The graph below shows the total number of articles in catalytic oxidation on metal-supported oxide films across all publications each year (not limited to Nature Index journals).

Technical terms

Strong metal–support interaction (SMSI): Electronic and structural modification at the metal–oxide interface that alters adsorption properties and catalytic activity.

Mars–van Krevelen mechanism: Oxidation pathway in which lattice oxygen from an oxide catalyst directly reacts with a substrate, creating vacancies that are replenished by gaseous O2.

Reducible oxide: Metal oxide capable of undergoing changes in oxidation state under reaction conditions, enabling oxygen exchange and vacancy formation.

Ultrathin film: Oxide layer of atomic or few-atomic thickness with properties distinct from bulk materials due to strong interfacial effects.

Tip-enhanced Raman spectroscopy (TERS): Surface-sensitive vibrational spectroscopy technique that combines Raman scattering with a plasmonic probe to achieve nanoscale chemical resolution.

Scanning tunnelling microscopy (STM): Imaging method relying on quantum tunnelling of electrons between a sharp tip and a surface to resolve atomic-scale topography and local electronic states.

References

1. Elucidating the active phases of CoOx films on Au(111) in the CO oxidation reaction. Nature Communications (2023).
2. Electron penetration triggering interface activity of Pt-graphene for CO oxidation at room temperature. Nature Communications (2021).
3. Nanoscale Chemical Probing of Metal-Supported Ultrathin Ferrous Oxide via Tip-Enhanced Raman Spectroscopy and Scanning Tunneling Microscopy. Chemical & Biomedical Imaging (2024).
4. Structural Changes in Monolayer Cobalt Oxides under Ambient Pressure CO and O2 Studied by In Situ Grazing-Incidence X‑ray Absorption Fine Structure Spectroscopy. The Journal of Physical Chemistry C (2022).
5. Probing Catalytic Sites and Adsorbate Spillover on Ultrathin FeO2–x Film on Ir(111) during CO Oxidation. ACS Nano (2024).