Single-Atom Photocatalysis for Energy Conversion

Single-atom photocatalysis harnesses the unique properties of isolated metal atoms anchored on semiconductor supports to drive light‐induced chemical transformations with unparalleled atom efficiency. By maximising the exposure of catalytic sites and tailoring local electronic environments, these materials achieve high activity and selectivity in key energy‐conversion reactions, including hydrogen evolution, carbon dioxide reduction and solar fuel synthesis. Advances in support design, defect engineering and coordination control have addressed longstanding challenges in catalyst stability and charge transfer, paving the way for scalable, cost‐effective systems that convert solar energy into chemical bonds with minimal energy losses.

Research from Nature Portfolio

Recent studies have demonstrated that copper single atoms dispersed on titanium dioxide attain exceptional hydrogen evolution performance, achieving more than 100 mmol g⁻¹ h⁻¹ under simulated sunlight and an apparent quantum efficiency exceeding 50 per cent at 365 nm. Remarkable long‐term stability over a year has been shown, with efficient electron transfer mediated by a Cu²⁺/Cu⁺ redox cycle underpinning the high activity.

Another development involves the precise modulation of copper coordination on graphitic carbon nitride supports. Two distinct single‐atom sites, Cu–N₄ and Cu–N₃, were prepared to steer carbon dioxide hydrogenation along methanol versus carbon monoxide pathways. The Cu–N₄ configuration delivered methanol productivity of over 4 mmol g⁻¹ h⁻¹ with selectivity above 95 per cent, highlighting the critical role of atomic coordination in dictating reaction outcomes.

Single-Atom Photocatalysis for Energy Conversion publication trend

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

Technical terms

Single‐Atom Catalyst: A catalytic material in which individual metal atoms are isolated on a support to maximise atomic utilisation and active‐site exposure.

Photocatalysis: Light‐driven acceleration of chemical reactions on a semiconductor surface via generation and separation of electron–hole pairs.

Active Site: A specific atomic or molecular location on a catalyst surface where reactant molecules adsorb and react.

Carbon Nitride: A polymeric semiconductor composed of carbon and nitrogen, often used as a support for single‐atom catalysts due to its cavity‐rich structure.

Quantum Efficiency: The ratio of reacted electrons or generated products to the number of incident photons, indicating photocatalytic performance.

Syngas: A mixture of carbon monoxide and hydrogen used as an intermediate feedstock for fuel and chemical synthesis.

References

1. Manipulating photogenerated electron flow in nickel single‐atom catalysts for photocatalytic CO2 reduction into tunable syngas. Carbon Energy (2024).
2. Single-atom Cu anchored catalysts for photocatalytic renewable H2 production with a quantum efficiency of 56%. Nature Communications (2022).
3. Coordination tailoring of Cu single sites on C3N4 realizes selective CO2 hydrogenation at low temperature. Nature Communications (2021).
4. Copper single-atoms embedded in 2D graphitic carbon nitride for the CO2 reduction. npj 2D Materials and Applications (2021).