Electrocatalytic Activity in Alkaline Fuel Cell Systems

Alkaline fuel cell systems harness the electrocatalytic activity of specialised materials to facilitate charge transfer at the anode and cathode. A prominent example is the anion exchange membrane fuel cell (AEMFC), in which hydroxide ions migrate through a polymer electrolyte under alkaline conditions. The oxygen reduction reaction (ORR) at the cathode often limits performance, demanding catalysts that combine high activity, durability and affordability. Research has shifted from platinum group metals towards earth-abundant alternatives such as heteroatom-doped carbons, single-atom catalysts and defect-engineered frameworks. Key strategies include maximising active site exposure, tuning electronic structures via nitrogen or dual-metal incorporation, and strengthening stability in alkaline media. These developments promise lower costs, reduced reliance on critical minerals and accelerated deployment of fuel cells in stationary power, transport and renewable energy integration, with potential coupling to metal–air batteries and electrolysers.

Research from Nature Portfolio

Recent studies have introduced an interfacial assembly approach to construct porous nanocages hosting binary single-atom Fe/Co–Nx sites with exceptionally high metal loading and accessible active site density. This architecture delivers peak power densities that are three times higher than control catalysts in both AEMFCs and zinc–air batteries, highlighting the role of maximised site utilisation. Foundational work has also demonstrated gram-scale synthesis of metal-free carbon nitride and carbon nanofibre hybrids via simple liquid-phase reactions. These hybrids exhibit outstanding methanol tolerance, selectivity and stability, achieving robust performance as cathodes in alkaline polymer electrolyte fuel cells and illustrating pathways towards scalable, non-metal electrocatalysts.

Electrocatalytic Activity in Alkaline Fuel Cell Systems publication trend

The graph below shows the total number of articles in electrocatalytic activity in alkaline fuel cell systems across all publications each year (not limited to Nature Index journals).

Technical terms

Electrocatalysis: The acceleration of electrochemical reactions at electrode surfaces by catalysts that lower activation energies and facilitate charge transfer.

Anion exchange membrane fuel cell (AEMFC): A fuel cell using a hydroxide-conducting polymer membrane to transport anions from cathode to anode in alkaline conditions.

Oxygen reduction reaction (ORR): The cathodic half-reaction in fuel cells where O₂ is reduced to hydroxide ions, often determining overall cell performance.

Single-atom catalyst: A catalyst in which individual metal atoms are atomically dispersed on a support, maximising active site utilisation and selectivity.

Site density: The number of catalytically active sites per unit mass or surface area of catalyst, influencing overall reaction rate and device output.

References

1. Interfacial assembly of binary atomic metal-Nx sites for high-performance energy devices. Nature Communications (2023).
2. Facile and Gram-scale Synthesis of Metal-free Catalysts: Toward Realistic Applications for Fuel Cells. Scientific Reports (2015).
3. Highly Active and Durable Metal‐Free Carbon Catalysts for Anion‐Exchange Membrane Fuel Cells. Advanced Energy Materials (2023).
4. Lignin-Derived Precious Metal-Free Electrocatalysts for Anion-Exchange Membrane Fuel Cell Application. ACS Catalysis (2024).