Designing rare-earth-based nanoalloys for advanced catalysis: trends, challenges, and perspectives

In recent years, rare-earth (RE) elements have demonstrated tremendous potential in constructing high-performance catalytic materials, owing to their unique 4f electronic configurations and low electronegativity. Incorporating RE elements into metallic alloy systems not only effectively regulates the electronic structure and atomic arrangement of the alloy but also significantly enhances its catalytic activity and structural stability. Compared with transition metal (M) alloys, RE alloys exhibit more negative formation enthalpies and superior thermodynamic stability, offering distinct advantages in improving the durability of catalytic materials. With the rapid development of nanocatalysis, rare-earth nanoalloys (RE-NAs), characterized by excellent structural controllability and multifunctionality, have emerged as an important research focus in fields such as energy catalysis and environmental remediation. However, the extremely low reduction potential of RE metals poses significant thermodynamic and kinetic challenges in the controllable synthesis of RE-NAs. To address this, researchers have proposed various strategies, including sodium vapor reduction, support-assisted synthesis, and metal-organic precursor approaches, achieving efficient reduction and alloying of RE ions and successfully preparing a series of RE-NA catalysts with high activity and stability. Despite remarkable progress in recent years, systematic reviews that integrate the key scientific mechanisms, structure-property relationships, and future research directions of RE-NAs remain lacking. This review comprehensively summarizes the thermodynamic basis of the formation of RE-NAs, structural regulation strategies, and their applications in typical electrocatalytic reactions and elucidates the mechanisms of structure-property regulation and performance enhancement. This review will provide theoretical guidance and inspiration for the in-depth study and rational design of RE nanoalloy catalytic systems.