Electrocatalytic Applications of High-Entropy Alloys

High-entropy alloys (HEAs) represent a novel class of metallic materials characterised by the near-equimolar incorporation of five or more principal elements into a single solid-solution phase. This configurational complexity imparts unique physicochemical properties, including enhanced structural stability, tunable electronic structure and a multiplicity of active sites. In electrocatalysis, HEAs have emerged as versatile platforms for reactions integral to sustainable energy conversion and chemical synthesis. Their compositional diversity allows fine-tuning of adsorption energies for reaction intermediates, while synergistic interactions among constituent elements often yield catalytic activities and stabilities that surpass those of conventional monometallic or binary systems. Practical implementations span hydrogen evolution and oxidation, oxygen evolution, carbon dioxide reduction and ammonia decomposition. Advances in synthesis—ranging from wet-chemical assembly of mesoporous nanospheres to controlled support deposition—have facilitated the generation of HEA nanostructures with optimised surface area, electronic conductivity and mass transport properties. As the world seeks carbon-neutral pathways and decentralised energy systems, HEA-based electrocatalysts offer promising routes to robust, earth-abundant and tunable solutions.

Research from Nature Portfolio

Recent studies have elucidated the fundamental origins of HEA performance by correlating electronegativity differences with intermediate adsorption. Work on FeCoNiXRu systems (X = Cu, Cr, Mn) has demonstrated that charge redistribution among mixed elements creates highly active sites that selectively stabilise both hydroxyl and hydrogen intermediates, thereby accelerating water dissociation under alkaline conditions. Separately, the design of PtPdRhRuCu mesoporous nanospheres has highlighted the importance of hierarchical porosity and multi-element synergy. These nanospheres exhibit exceptionally low overpotentials for the hydrogen evolution reaction across acidic, alkaline and neutral media, attributable to rapid mass and electron transport within the interconnected pore network. Collectively, these advances underscore the capacity of HEAs to break conventional scaling relations and achieve high activity and durability in electrochemical environments.

Electrocatalytic Applications of High-Entropy Alloys publication trend

The graph below shows the total number of articles in electrocatalytic applications of high-entropy alloys across all publications each year (not limited to Nature Index journals).

Technical terms

High-Entropy Alloy (HEA): A metallic solid solution comprising five or more principal elements in near-equiatomic proportions, stabilised by high configurational entropy.

Electrocatalysis: Acceleration of electrochemical reactions at an electrode surface through the use of a catalyst.

Overpotential: The extra voltage beyond the thermodynamic potential required to drive an electrochemical reaction at a given rate.

Active Site: A specific atomic or molecular configuration on a catalyst surface where reactant adsorption and conversion occur.

Hydrogen Evolution Reaction (HER): Electrochemical generation of hydrogen from protons and electrons, typically occurring at the cathode.

Oxygen Evolution Reaction (OER): Electrochemical production of oxygen from water molecules, typically occurring at the anode.

References

1. Unraveling the electronegativity-dominated intermediate adsorption on high-entropy alloy electrocatalysts. Nature Communications (2022).
2. Mesoporous multimetallic nanospheres with exposed highly entropic alloy sites. Nature Communications (2023).
3. High-Entropy Electrode Materials: Synthesis, Properties and Outlook. Nano-Micro Letters (2024).
4. High-entropy energy materials: challenges and new opportunities. Energy & Environmental Science (2021).
5. Synthesis of high-entropy alloy nanoparticles on supports by the fast moving bed pyrolysis. Nature Communications (2020).