Catalytic Oxidation Mechanisms on Platinum-Based Nanoparticles

Platinum-based nanoparticles have become central to heterogeneous catalysis owing to their exceptional activity and selectivity in oxidation reactions. At the heart of their performance lies the interplay between particle size, morphology and support interactions, which together govern adsorption energies, reaction pathways and catalyst stability. Oxidative catalysis on platinum typically proceeds by adsorption of reactants (for example CO and O₂), formation of transient intermediates on the surface and desorption of products such as CO₂. Two principal mechanistic paradigms are often invoked: in the Langmuir–Hinshelwood model, both reactants adsorb and migrate on the surface before reacting; in the Mars–van Krevelen model, lattice oxygen from a surface oxide participates directly in the oxidation cycle. Under realistic conditions platinum surfaces undergo dynamic restructuring, forming ultrathin surface oxides that can either enhance or attenuate activity. Such nanoscale and atomistic insights underpin the optimisation of emission-control catalysts, fuel-cell electrodes and industrial oxidations of volatile organic compounds.

Research from Nature Portfolio

Recent studies have applied microsecond-resolution ambient pressure X-ray photoelectron spectroscopy to track active intermediates on Pt(111) under reaction conditions, revealing that chemisorbed atomic oxygen, rather than a bulk surface oxide, is the principal species reacting with CO to form CO₂, thus confirming a Langmuir–Hinshelwood mechanism. In situ scanning tunnelling microscopy investigations have identified two distinct two-dimensional surface oxides—spoked-wheel and stripe motifs—on platinum single crystals at elevated temperature and pressure. These surface phases are only stable under an oxygen atmosphere and are implicated as the active species during catalytic oxidation, refining our understanding of the active phase and its transformation under working conditions.

Catalytic Oxidation Mechanisms on Platinum-Based Nanoparticles publication trend

The graph below shows the total number of articles in catalytic oxidation mechanisms on platinum-based nanoparticles across all publications each year (not limited to Nature Index journals).

Technical terms

Chemisorption: Strong adhesion of a reactant species to a catalyst surface via chemical bonding, essential for forming reaction intermediates.

Langmuir–Hinshelwood mechanism: A reaction pathway in which adsorbed reactants on the catalyst surface migrate and react to form products.

Ambient pressure X-ray photoelectron spectroscopy: An in situ surface-analysis technique performed at gas pressures near atmospheric levels to study catalysts under working conditions.

Surface oxide: A thin, ordered oxide layer formed on the metal catalyst surface under oxidising conditions, often influencing activity and selectivity.

Step/kink sites: Low-coordination atomic sites at surface imperfections that serve as high-activity centres for adsorption and reaction.

References

1. Resolving active species during the carbon monoxide oxidation over Pt(111) on the microsecond timescale. Nature Communications (2025).
2. CO and O2 Interaction with Kinked Pt Surfaces. ACS Catalysis (2024).
3. Observing the oxidation of platinum. Nature Communications (2017).
4. Pt nanoparticles under oxidizing conditions – implications of particle size, adsorption sites and oxygen coverage on stability. Nanoscale Advances (2022).
5. Oxidation of Gas-Phase and Supported Pt Nanoclusters: An Ab Initio Investigation. The Journal of Physical Chemistry C (2022).