Oxygen Vacancy Dynamics in Ceria Catalysts

Ceria (CeO₂) is distinguished by its facile redox cycling between Ce⁴⁺ and Ce³⁺ and by its remarkable ability to accommodate and transport oxygen through vacancy formation and migration. Oxygen vacancies form when lattice oxygen atoms are removed under reducing conditions, creating local sites that can store and release oxygen during catalytic cycles. The dynamics of these vacancies—formation energy, mobility at surfaces and subsurfaces, interaction with dopants, and coupling to lattice strain—govern key processes in heterogeneous catalysis, three-way automotive converters, solid oxide fuel cells and emerging applications in photocatalysis and spintronics. Experimental probes such as neutron scattering, solid-state NMR and high-resolution microscopy, together with atomistic simulations, have revealed that vacancy distributions are highly sensitive to particle size, surface termination and external stimuli (temperature, strain, adsorbates). Control of vacancy behaviour under realistic reaction conditions is therefore central to maximising ceria’s oxygen-storage capacity, catalytic selectivity and long-term stability.

Research from Nature Portfolio

Recent studies have shown that charge transfer between oxygen vacancies and cerium 4f orbitals can stabilise non-cubic polymorphs, leading to reversible phase transitions with concomitant negative thermal expansion in nanoscale ceria. Advanced local-structure analysis combining pair distribution functions and Raman spectroscopy has demonstrated that subsurface vacancy order drives these anomalous effects. Complementary work using dynamic nuclear polarisation-enhanced solid-state NMR and density functional theory has mapped polar surface reconstructions on ceria nanocubes, quantifying the coexistence of hydroxyls and CeO₄ terminations required for polarity compensation. Another investigation has revealed that thermally activated oxygen vacancy migration at elevated temperatures induces non-conventional ferromagnetism in nanocrystalline films, where mobile vacancies underpin magnetic polaron networks and suggest new multifunctional uses of ceria beyond classical catalysis.

Oxygen Vacancy Dynamics in Ceria Catalysts publication trend

The graph below shows the total number of articles in oxygen vacancy dynamics in ceria catalysts across all publications each year (not limited to Nature Index journals).

Technical terms

Oxygen vacancy: A site in the ceria lattice where an O²⁻ ion is missing, creating a defect that enhances redox activity and oxygen transport.

Polaron: A localised charge carrier (electron or hole) coupled to lattice distortion, in ceria typically associated with a reduced Ce³⁺ centre adjacent to a vacancy.

Density functional theory (DFT): A first-principles computational method for determining electronic structure, widely used to calculate vacancy formation energies and migration pathways.

Langmuir–Hinshelwood mechanism: A surface reaction model in which both reactant species adsorb at neighbouring sites before reacting, here facilitated by the dynamic movement of oxygen vacancies.

References

1. Charge transfer drives anomalous phase transition in ceria. Nature Communications (2018).
2. Polar surface structure of oxide nanocrystals revealed with solid-state NMR spectroscopy. Nature Communications (2019).
3. Oxygen diffusion and vacancy migration thermally-activated govern high-temperature magnetism in ceria. Scientific Reports (2019).
4. Environment-Driven Variability in Absolute Band Edge Positions and Work Functions of Reduced Ceria. Journal of the American Chemical Society (2024).
5. The Structure of Oxygen Vacancies in the Near-Surface of Reduced CeO2 (111) Under Strain. Frontiers in Chemistry (2019).
6. Catalytic role of vacancy diffusion in ceria supported atomic gold catalyst. Chemical Communications (2017).