Catalytic Surface Reactions in Heterogeneous Catalysis

The understanding of catalytic surface reactions lies at the heart of heterogeneous catalysis, where reactant molecules interact with solid surfaces to undergo transformation into desired products. Such reactions proceed via elementary steps—adsorption of reactants, surface diffusion, reaction of adsorbed species and desorption of products—each governed by the chemical identity and arrangement of active sites on the catalyst surface. Advances in surface methods and in situ characterisation have revealed the dynamic nature of these active sites, which may reconstruct, oxidise or reform under reaction conditions. Reaction kinetics are determined by a balance between surface coverage of intermediates, the energy barriers for individual steps and mass‐transport limitations within complex reactor environments. Theoretical approaches, including density functional theory and microkinetic modelling, have provided detailed maps of reaction pathways, quantifying the influence of surface facets, strain and electronic effects on catalytic performance. Such insights underpin the rational design of catalysts for applications ranging from emission control and fuel conversion to selective chemical synthesis and environmental remediation. Emerging evidence of spatio‐temporal phenomena on nanometre‐scale surfaces underscores the need to integrate high-resolution imaging with time-resolved spectroscopy to capture the interplay between surface chemistry and local reactant distributions.

Research from Nature Portfolio

Recent studies have uncovered complex dynamic behaviours on model nanocrystal surfaces. In one example, a rhodium nanoscale surface consisting of coupled nanofacets exhibited multiple reaction modes, including transitions to spatio-temporal chaos, driven by variations in hydrogen pressure and diffusive coupling. Microkinetic simulations for an array of oscillators revealed how local coupling controls the emergence of chaotic and periodic states, with implications for other compartmentalised reaction systems. Another investigation applied time-resolved ambient pressure photoelectron spectroscopy to a palladium(100) model during CO oxidation. By cyclic gas pulsing and event-averaging, researchers captured transient lifting of CO poisoning and the rapid formation of surface oxides within seconds. These findings highlight the capacity of operando spectroscopy to probe active site evolution and the interplay between surface phase changes and catalytic activity under realistic pressures.

Catalytic Surface Reactions in Heterogeneous Catalysis publication trend

The graph below shows the total number of articles in catalytic surface reactions in heterogeneous catalysis across all publications each year (not limited to Nature Index journals).

Technical terms

Heterogeneous catalysis: Catalytic reactions occurring at the interface between a solid catalyst and gaseous or liquid reactants.

Active site: Specific atomic arrangement on a catalyst surface where reactants adsorb and react.

Adsorption: Attachment of a molecule onto a surface via chemical or physical interactions.

Desorption: Release of a product molecule from the catalyst surface into the gas or liquid phase.

Turnover frequency (TOF): Number of reactant molecules converted per active site per unit time.

Spatio-temporal chaos: Irregular, unpredictable oscillatory patterns in reaction rates and species distributions across a surface.

Pairwise hydrogen addition: Mechanism in which both hydrogen atoms from a single H₂ molecule add to an unsaturated substrate without surface scrambling.

References

1. Emergence of chaos in a compartmentalized catalytic reaction nanosystem. Nature Communications (2023).
2. Stroboscopic operando spectroscopy of the dynamics in heterogeneous catalysis by event-averaging. Nature Communications (2021).
3. Contrasting Metallic (Rh0) and Carbidic (2D-Mo2C MXene) Surfaces in Olefin Hydrogenation Provides Insights on the Origin of the Pairwise Hydrogen Addition. ACS Catalysis (2024).
4. A Polycrystalline Pd Surface Studied by Two-Dimensional Surface Optical Reflectance during CO Oxidation: Bridging the Materials Gap. ACS Applied Materials & Interfaces (2023).
5. Experimental investigation of NO reduction by H2 on Pd using planar laser-induced fluorescence. Applications in Energy and Combustion Science (2023).