Single-Atom Catalysts for Electrocatalytic Reactions

Single-atom catalysts (SACs) represent a frontier in electrocatalysis, combining maximal atom efficiency with tailored electronic structures at isolated metal centres. By anchoring individual metal atoms on conductive supports such as doped carbons, metal-organic frameworks or layered hydroxides, SACs achieve unparalleled site uniformity and enhanced turnover frequencies. The atomistic dispersion ensures every metal centre participates in the reaction, maximising resource utilisation and reducing precious-metal loadings. Key electrocatalytic processes addressed by SACs include hydrogen evolution, oxygen evolution and oxygen reduction, where control over adsorption energetics of reaction intermediates is critical. Rational design of coordination environments, electronic coupling between metal atoms and supports, and synergistic interactions in bimetallic systems underpin advances in activity, selectivity and long-term stability. The global drive for sustainable energy conversion and chemical synthesis has rendered SACs highly significant, offering routes to low-overpotential water splitting, efficient fuel-cell cathodes and selective fine-chemical generation under mild conditions. Emerging trends focus on main-group metals in SAC configurations, dual-atom or bimetallic sites that harness cooperative effects, and scalable fabrication techniques to bridge laboratory discoveries with industrial application.

Research from Nature Portfolio

Recent studies have demonstrated transformative outcomes by engineering the coordination and electronic environment of single atoms. An iridium-based SAC coordinated out-of-plane by organic ligands on cobalt-iron hydroxide support achieved record low overpotentials for the oxygen evolution reaction, alongside ultrahigh mass activity that far exceeds conventional oxide benchmarks. Computational insights revealed that the ligand-induced electron redistribution optimises the d-band centre at active sites, facilitating energetically favourable reaction pathways. In another seminal advance, a sulphur-doped carbon template was used to stabilise atomically dispersed platinum, enabling selective peroxide formation in oxygen reduction under extended operation. The unique curved graphene network and high sulphur content anchor platinum as isolated atoms, steering the four-electron pathway away from water formation and opening routes to fine-chemical electrosynthesis. Earlier foundational work established cobalt and nickel single-atom centres on nitrogen-doped graphene as highly active and durable catalysts for hydrogen evolution, illustrating the broad potential of earth-abundant metals in single-atom form.

Single-Atom Catalysts for Electrocatalytic Reactions publication trend

The graph below shows the total number of articles in single-atom catalysts for electrocatalytic reactions across all publications each year (not limited to Nature Index journals).

Technical terms

Single-atom catalyst (SAC): A material in which catalytically active metal atoms are isolated and atomically dispersed on a support, maximising atom utilisation and enabling uniform active sites.

Overpotential: The additional potential beyond the thermodynamic requirement needed to drive an electrochemical reaction at a given current density; lower values indicate higher catalytic efficiency.

Tafel slope: A parameter derived from the logarithmic relation between current density and overpotential, reflecting reaction kinetics and rate-determining steps.

d-band centre: The energy position of the centre of the d-electron density of states in transition metals, used to predict adsorption strength of intermediates and catalytic activity.

Coordination environment: The local atomic arrangement and ligand interactions around a metal centre, influencing its electronic properties and catalytic behaviour.

References

1. Progress of Main-Group Metal-Based Single-Atom Catalysts. Electrochemical Energy Reviews (2024).
2. Bimetallic Single-Atom Catalysts for Water Splitting. Nano-Micro Letters (2024).
3. Out-of-plane coordination of iridium single atoms with organic molecules and cobalt–iron hydroxides to boost oxygen evolution reaction. Nature Nanotechnology (2024).
4. Tuning selectivity of electrochemical reactions by atomically dispersed platinum catalyst. Nature Communications (2016).
5. Atomic cobalt on nitrogen-doped graphene for hydrogen generation. Nature Communications (2015).
6. Atomically isolated nickel species anchored on graphitized carbon for efficient hydrogen evolution electrocatalysis. Nature Communications (2016).