Electrochemical Oxidation of Carbon Monoxide on Catalytic Surfaces

The electrochemical oxidation of carbon monoxide on catalytic surfaces is a cornerstone of electrocatalysis, with implications spanning fuel‐cell technology, pollution abatement and sensor development. Carbon monoxide binds strongly to noble‐metal surfaces, notably platinum, inhibiting active sites and diminishing catalytic efficiency in proton‐exchange membrane fuel cells. Oxidation proceeds via Langmuir–Hinshelwood or Eley–Rideal mechanisms, in which adsorbed CO is converted to CO₂ through reactive oxygen species generated at the electrode–electrolyte interface. Key parameters include the onset potential for CO oxidation, the coverage and mobility of CO adlayers, and the influence of surface morphology and alloy composition. Studies reveal that low‐index facets exhibit distinct onset potentials and stability, while bimetallic and nanostructured catalysts can lower the oxidation overpotential and enhance tolerance to CO poisoning. In situ spectro‐electrochemical methods, coupled with theoretical modelling, have elucidated dynamic restructuring of adlayers, transient intermediates and the role of point defects. Control of catalyst morphology at the atomic scale and optimisation of the electrolyte environment have yielded substantial improvements in activity and durability. Ongoing efforts aim to integrate advanced characterisation and design principles to achieve efficient CO removal under fuel‐cell operating conditions and to inform the development of next‐generation electrocatalysts.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Electrochemical Oxidation of Carbon Monoxide on Catalytic Surfaces publication trend

The graph below shows the total number of articles in electrochemical oxidation of carbon monoxide on catalytic surfaces across all publications each year (not limited to Nature Index journals).

Technical terms

Electrocatalysis: Acceleration of electrochemical reactions by a specialised electrode surface.

Adsorbate: A molecule bound to a catalyst surface during a reaction.

Eley–Rideal mechanism: Reaction pathway in which a solution-phase reactant reacts directly with an adsorbed species.

Langmuir–Hinshelwood mechanism: Reaction between two adsorbed species on a surface.

Onset potential: The electrode potential at which a significant Faradaic current for oxidation begins.

Surface-enhanced infrared absorption spectroscopy (SEIRAS): Technique that amplifies infrared signals of surface species via nanostructured electrodes.

Cyclic voltammetry: Electrochemical method involving potential sweeps to probe redox behaviour and reaction kinetics.

Bifunctional mechanism: Cooperative catalytic effect in bimetallic systems where one element activates CO and the other provides oxygenated species.

References

1. Improved In Situ Characterization of Electrochemical Interfaces Using Metasurface‐Driven Surface‐Enhanced IR Absorption Spectroscopy. Advanced Functional Materials (2023).
2. Multi-band Metasurface-Driven Surface-Enhanced Infrared Absorption Spectroscopy for Improved Characterization of in-Situ Electrochemical Reactions. ACS Photonics (2024).
3. Electro-Oxidation of CO Saturated in 0.1 M HClO4 on Basal and Stepped Pt Single-Crystal Electrodes at Room Temperature Accompanied by Surface Reconstruction. Surfaces (2019).
4. Behaviour of Pt10-xRux/C catalysts towards the hydrogen oxidation reaction in acidic medium in the presence of adsorbed CO. Electrochimica Acta (2024).
5. The Dynamic Nature of CO Adlayers on Pt(111) Electrodes. Angewandte Chemie International Edition (2020).