Gold Catalysis in Low-Temperature Water-Gas Shift Reactions

Gold catalysts, typically in the form of nanoparticles dispersed on metal-oxide supports, have been identified as exceptionally active for the water-gas shift reaction at temperatures below 200 °C. The low-temperature WGS process is vital for downstream purification of hydrogen streams and for maximising hydrogen yield in clean-energy applications. At such conditions, catalysis is governed by intimate gold–support interactions, often centred on oxygen vacancy sites in reducible oxides such as ceria or titania. Mechanistic studies reveal two principal pathways: a redox mechanism involving cyclic oxidation and reduction of the gold–support interface, and a carboxyl pathway proceeding via formate intermediates. The size and electronic state of gold particles critically influence activity, with sub-5 nm clusters exhibiting optimal performance. Stability issues arise from particle sintering, but recent advances in support design, dopant incorporation and operando regeneration strategies have begun to address these challenges. Overall, gold-based low-temperature WGS catalysis combines high selectivity, mild operating conditions and potential for on-stream regeneration, underscoring its industrial and environmental significance.

Research from Nature Portfolio

Recent studies have employed operando X-ray absorption and infrared spectroscopies to trace atomic-scale evolution of platinum and copper dopants within gold nanoclusters on ceria supports during low-temperature WGS. It was shown that copper migrates away from the cluster into the support, forming separate clusters, whereas platinum remains as single-atom sites on the gold surface. These dynamic redistributions alter gold–support interfaces and cluster morphology under reaction conditions, directly influencing turnover rates and catalyst stability. The findings underscore the importance of dopant selection and pretreatment protocols for optimising active site structure and prolonging catalytic performance at temperatures below 200 °C.

Gold Catalysis in Low-Temperature Water-Gas Shift Reactions publication trend

The graph below shows the total number of articles in gold catalysis in low-temperature water-gas shift reactions across all publications each year (not limited to Nature Index journals).

Technical terms

Water–Gas Shift Reaction (WGS): Catalytic reaction converting CO and H2O into CO2 and H2, crucial for hydrogen production and purification.

Nanocluster: Aggregation of a few to a few dozen atoms forming particles typically below 5 nm, with distinct electronic properties.

Localized Surface Plasmon (LSP): Collective oscillation of conduction electrons in metal nanoparticles excited by light, enhancing local electromagnetic fields and catalytic rates.

Oxygen Vacancy: Missing oxygen atom in a metal-oxide lattice, creating an active site for adsorption and redox reactions.

Operando Spectroscopy: In situ analytical methods that probe catalysts under working conditions to reveal real-time structural or electronic changes.

Non-Thermal Plasma: Partially ionised gas with energetic electrons that can activate reaction intermediates at low bulk temperatures.

References

1. Recent Advances in the Gold-Catalysed Low-Temperature Water–Gas Shift Reaction. Catalysts (2018).
2. Dynamic behaviour of platinum and copper dopants in gold nanoclusters supported on ceria catalysts. Communications Chemistry (2023).
3. Plasmonic-Assisted Water–Gas Shift Reaction of Gold Particles on TiO2. Catalysts (2023).
4. Non‐Thermal Plasma Activation of Gold‐Based Catalysts for Low‐Temperature Water–Gas Shift Catalysis. Angewandte Chemie International Edition (2017).
5. Reversible Growth of Gold Nanoparticles in the Low-Temperature Water–Gas Shift Reaction. ACS Nano (2022).