Intermetallic electrocatalysts for small-molecule fuel oxidation

Intermetallic compounds with well-ordered crystal structures and precise stoichiometry are emerging as a transformative class of electrocatalysis. Existing reviews have primarily focused on intermetallic compounds for specific electrocatalytic reactions or their synthesis strategies, while a comprehensive perspective on how ordered structures contribute to performance across different electrochemical applications that share similarity remains underexplored. In this review, the recent progress is examined in intermetallic compounds, particularly focusing on their structure–property-performance correlations in four critical small-molecule fuel oxidation reactions, including hydrogen oxidation reactions, formic acid oxidation reactions, methanol oxidation reactions, and ethanol oxidation reactions. These reactions are central to sustainable fuel-cell technologies due to their high theoretical energy densities, relatively benign byproducts, and scalability for clean energy production. This review begins by highlighting the advantages of intermetallic compound nanocrystals over metal alloys, such as their unique crystal structures, exceptional thermodynamic stability, enhanced durability, improved intrinsic activity, optimized distribution of active sites, and benign scalability. Subsequently, their applications in these small-molecule fuel oxidation reactions are comprehensively discussed in detail. This review concludes with an outlook on future directions for the synthesis and application of intermetallic nanocrystals, emphasizing their critical role in advancing sustainable energy technologies.