Advanced Development of High-Entropy Alloys in Catalytic Applications

Conventional alloys have long been limited by their simple compositions, which make it difficult to meet the requirements of modern catalysis applications. In contrast, high-entropy alloys (HEAs), characterized by multi-principal elements in near-equimolar ratios, have become a transformative paradigm in materials science since their inception in 2004. The unique core effects of HEAs, including the high-entropy effect, severe-lattice distortion effect, sluggish-diffusion effect, and cocktail effect, endow them with superior catalytic properties of activity, selectivity, and durability. However, with the rapid advanced development of HEAs, a comprehensive review of their applications in catalysis is imperative to foster a deeper understanding. In this review, the catalytic capability of HEAs, commencing from the entropy-driven mechanism and core effects of HEAs is systematically explored. Then, their applications are comprehensively analyzed in diverse fields, including energy conversion, chemical industries, and environmental remediation, emphasizing their remarkable capabilities in catalytic applications. Finally, pivotal challenges are outlined in synthesis methods, mechanistic elucidation, and green manufacturing, and propose future directions such as database establishment and machine-learning-assisted design. By addressing knowledge gaps and inspiring innovative strategies, this review aims to accelerate the translation of HEAs into practical solutions for a sustainable energy and environmental future.