Electrocatalytic Properties of Metal Aerogels

Metal aerogels are three-dimensional, porous networks of noble or base metals that combine exceptionally high specific surface areas with interconnected conductive pathways. Their open, nanoscale framework enhances mass transport and exposes abundant catalytic sites, making them ideal candidates for a range of electrochemical reactions. By tuning composition—ranging from monometallic gold, silver or platinum to multimetallic alloys such as Pt–Ni or Pd–Pt—researchers can optimise intrinsic activity, selectivity and durability. Ligand chemistry, reductant choice and fabrication conditions offer control over pore architecture, alloy homogeneity and surface chemistry, which in turn influence key reactions including the oxygen reduction reaction in fuel cells, the oxygen evolution reaction in electrolyzers and the electrooxidation of small organic molecules such as ethanol, methanol and formic acid. Recent advances have demonstrated that organic modifiers can enhance catalytic performance by stabilising active sites, while alloying strategies can reduce reliance on scarce metals and improve resistance to dissolution. The combination of high conductivity, mechanical stability and extensive active interfaces positions metal aerogels as a versatile platform for sustainable energy conversion and storage technologies.

Research from Nature Portfolio

Recent studies have unveiled a reductant-directed gelation strategy to fabricate noble metal aerogels with record-high surface areas. By employing an excess of organic reductant during gelation, researchers achieved gold aerogels exceeding 59.8 m2 g–1 and extended the method to silver, palladium and platinum compositions. These materials exhibited enhanced performance in ethanol oxidation and water splitting, revealing an unexpected ligand-enhancing effect that stabilises active facets and promotes charge transfer. In a separate development, inexpensive Fe–Pd nanoflakes were generated in situ on a leached graphite matrix, producing unsupported electrocatalysts with large surface areas and uniform metal dispersion. The resulting electrodes demonstrated exceptional activity for both methanol and formic acid oxidation, attributed to the synergistic interplay between iron and palladium and to the porous graphite support that prevents catalyst poisoning and facilitates rapid mass transport.

Electrocatalytic Properties of Metal Aerogels publication trend

The graph below shows the total number of articles in electrocatalytic properties of metal aerogels across all publications each year (not limited to Nature Index journals).

Technical terms

Aerogel: A highly porous, low-density solid formed by replacing the liquid in a gel with gas while preserving its network structure.

Electrocatalysis: Acceleration of an electrochemical reaction at an electrode surface by a catalyst.

Specific Surface Area: The total surface area of a material per unit mass, often measured in m2 g−1, critical for quantifying active site availability.

Oxygen Reduction Reaction (ORR): The electrochemical reaction in which O2 is reduced, typically to water or hydroxide, at the cathode of fuel cells.

Cryoaerogelation: A fabrication technique involving flash-freezing and freeze-drying of nanoparticle gels to yield porous aerogel films with controlled architecture.

References

1. Unveiling reductant chemistry in fabricating noble metal aerogels for superior oxygen evolution and ethanol oxidation. Nature Communications (2020).
2. Fe–Pd nanoflakes decorated on leached graphite disks for both methanol and formic acid electrooxidation with excellent electrocatalytic performance. Scientific Reports (2023).
3. A Decade of Electrocatalysis with Metal Aerogels: A Perspective. Catalysts (2023).
4. Tailoring Bimetallic Pt/Pd Cryogels for Efficient Ethanol Electro‐Oxidation. ChemElectroChem (2024).
5. Expanding the Range: AuCu Metal Aerogels from H2O and EtOH. Catalysts (2022).